Page 1 SB4241E00 Apr. 2007 Service Manual G420FE LP/Dual Fuel Engine G420F LP/Gasoline Dual Fuel Engine G15S-5, G18S-5, G20SC-5 GC15S-5, GC18S-5, GC20SC-5 G20E-5, G25E-5, G30E-5 GC20E-5, GC25E-5, GC30E-5, GC33E-5...
Page 2: Important Safety Information
If a tool, procedure, work method or operating technique not specifically recommended by DOOSAN is used, you must satisfy yourself that it is safe for you and others. You should also ensure that the product will not be damaged or made unsafe by the operation, lubrication, maintenance or repair procedures you choose.
Page 4: Table Of Contents
Checking and Adjusting Drive Belt ....23 Exhaust Manifold .......... 52 Adjusting............24 Cooling System ..........54 Checking Belt for Damage ......24 General Description ........54 Ignition System Maintenance ......25 Testing and Adjusting ........55 Inspect Battery System ......... 25 G420F(FE) Service Manual Index...
Page 5 Exhaust System...........187 Inspection of Ignition Coil ......123 SECM............187 Inspection of Spark Plug ......124 Charging System ..........126 SECM Wiring Diagrams for G420F ....188 General Description ........126 EMS Inspection and Repair......189 Troubleshooting .......... 128 Engine Control Module (SECM) ....189 Disassembly and Installation .......
Page 6 N-2007 Regulator for G420FE Engine Connector Inspection Procedure....251 ............. 218 Symptom Troubleshooting Guide Chart ..255 Basic Troubleshooting ........261 G420F LPG System Inspection and Repair..220 Intermittents..........261 Removal and Installation ......220 Surges and/or Stumbles ......262 G420F Fuel System Connections.. 221...
Page 7 SECM field update with Service Tool... 313 SECM field update with Service Tool... 314 Ground Speed Limits (Option) ......318 LPG And LPG Fuel Tanks........ 320 Regulatory Compliance ........324 Special Conditions for Safe Use ..... 324 Abbreviations........... 325 G420F(FE) Service Manual Index...
Page 8: Precautions Before Service
Be sure to use Special Tools when their use is specified for the operation. Use of substitute tools will result in malfunction of the part or damage it. G420F(FE) Service Manual Chapter 1. General Information...
Page 9: Electrical System
3. Locking connectors will click when the connector is secure. 4. Handle sensors and relays carefully. Be careful not to drop them or hit them against other parts. Before reassembly, apply specified oil to the rotating and sliding parts. G420F(FE) Service Manual Chapter 1. General Information...
Page 10 6. Avoid coasting with the ignition turned off and during prolonged braking 7. Do not dispose of a used catalytic converter together with parts contaminated with gasoline or oil. G420F(FE) Service Manual Chapter 1. General Information...
Page 11: Tightening Torque
NOTE: The torques shown in the table are not 1. If spring washers are used : 85% applicable, 2. If threads and bearing surfaces are stained with oil: 85% G420F(FE) Service Manual Chapter 1. General Information...
Page 12: Recommended Lubricants And Capacities
Coolant (Antifreeze) suitable for gasoline engines Concentration level 40%(tropical) having aluminum alloy parts Lubricant Capacities Description G(C)18S-5, G(C)20SC-5 G(C)20/25/30E-5 Oil Pan Engine Oil (liters) Oil Filter Total Engine Coolant (liters) Radiator & Hoses Total G420F(FE) Service Manual Chapter 1. General Information...
Page 13: Engine Model And Engine Serial Number
G420FE/G420F 30700001 to 39999999 • Electronic Control by ECM • Certified LP/Dual Fuel System available Features and Benefits of G420FE/G420F Engine – Closed loop LP Carburetion system • Al head with valve seat inserts – Closed loop MPI Gasoline system –...
Page 14: General Specification
API - SJ, SAE 10W30 or SAE 5W30 COOLING SYSTEM WATER PUMP ROTATION: V-Belt Drive - Clockwise (CW) when viewed from engine front THERMOSTAT: Opening Temperature: 82°C (180°F) Fully Open Temperature: 95°C (203°F) COOLING WATER CAPACITY: 3.0 L (block only) G420F(FE) Service Manual Chapter 1. General Information...
Page 15 LP FUEL LOCK-OFF: 12 V operation volt ENGINE OIL PR. S/W: 28.4 kPa (4.1 psi) STARTING MOTOR: 12 Volts, 1.7 kW ALTERNATOR: 13.5 Volts, 90 Amp EXHAUST SYSTEM Muffler Catalytic Muffler Muffler (without catalyst) G420F(FE) Service Manual Chapter 1. General Information...
Page 16: Engine Power And Torque
MAX TORQUE lbf-ft kgf-m 15,0 16.0 16.0 1600 1600 1600 GOVERNED SPEED 2450 2600 2600 LOW IDLE G420F Engine Power & Torque FORKLIFT MODEL G(C)15/18S-5 G420F-DF(LP) ENGINE MODEL G420F-DF(Gas) G420F-GAS & G420F-LP RATED POWER 33.6 35.8 36.5 45.6 48.7 49.7...
Page 17: General Maintenance
• Inspect the entire engine for oil and/or coolant leaks. • Repair as necessary before continuing. Inspect Vacuum Lines and Fittings • Visually inspect vacuum lines and fittings for physical damage such as brittleness, cracks and kinks. Repair/replace as required. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 18: Engine Oil Classification
1. Observe the API classification guide. 2. Proper SAE classification number should be selected within ambient temperature ranges. Do not use the lubricant with SAE classification number and API grade not identified on the container. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 19: Checking Engine Oil Level
3. Check the engine for oil contamination and viscosity and replace if necessary. 39.2~44.1N.m(4.0~4.5kgf.m, Torque 28.9~32.5lb-ft) 2)Fill with fresh engine oil. Capacity Drain 4.0L(4.23US qts, 3.52Lmp qts) and refill Oil filter 0.3L(0.32US qts, 0.26Lmp qts) G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 20: Checking Compressed Pressure
6. Install the compression gauge to the spark plug hole. 7. With the throttle valve opened, crank the engine to measure the compressed pressure. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 21: Adjusting Timing Belt Tension
6. If the arm indicator is out of the middle, loosen the bolt and repeat the previous procedure. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 22: Cooling System Maintenance
DOOSAN prefers the use of distilled water or deionized water to reduce the potential and severity of chemical insolubility.
Page 23: Checking Coolant Leaks
1.046 1.042 1.036 1.063 1.058 1.054 1.049 1.044 1.071 1.067 1.062 1.057 1.052 1.079 1.074 1.069 1.064 1.058 1.087 1.082 1.076 1.070 1.064 1.095 1.090 1.084 1.077 1.070 1.103 1.098 1.092 1.084 1.076 G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 24: Checking And Adjusting Drive Belt
40~50kg CAUTION The belt used over 5 minutes should be ad- justed as used belt of standard Check that the belt is installed correctly. When the belt is loosened, slip noise is heard. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 25: Adjusting
If the belt is too loose, due to early wear of belt and insufficient power of alternator, battery and water pump become inefficient and finally en- gine is overheated or damaged. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 26: Ignition System Maintenance
RPM. 3) Inspect the standard ignition timing. BTDC 5˚±5˚ 4) If ignition timing is out of the standard, inspect sensors concerned with ignition timing. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 27: Inspection Of Spark Plug
When installing a new sparkplug, install it after CAUTION checking the uniform plug clearance. Take care not to come foreign materials into spark-plug mounting hole. Spark plug clearance 0.7~0.8mm G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 28 • Density of the • Density of the Description fuel mixture is fuel mixture is thin thick • Lack of air • Ignition timing is intake fast • Spark plug is tight • Lack of torque G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 29: Fuel System Maintenance
5. Remove top cover (2), magnet (3), spring (4), and filter element (7) from bottom cover (5). 6. Replace the filter element (7). 7. Check bottom cover O-ring seal (6) for damage. Replace if necessary. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 30: Testing Fuel Lock-Off Operation
2. Disconnect the vacuum line from the FTVs to the fuel lock-off connector. pressure regulator/converter at the converter’s tee connection. 3. Lightly blow through the vacuum line connected to the FTVs. Air should not pass through the FTVs when de- energized. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 31: Inspect Air/Fuel Valve Mixer Assembly
Replace as necessary. • Apply a thin coat of an approved silicon lubricant to the TMAP O-ring seal. • Re-install the TMAP sensor into the manifold or manifold adapter and securely tighten the retaining screw. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 32: Maintenance Schedule
NOTE: The MI-07 fuel system was designed for use with LPG fuel that complies with HD5 or HD10 LPG fuel standards. Use of non-compliant LPG fuel may require more frequent service intervals and will disqualify the user from warranty claims. G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 33 G420F(FE) Service Manual Chapter 2. Recommended Maintenance...
Page 34: General Information
Chapter 3. ENGINE MECHANICAL SYSTEM General Information Engine Outline G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 35 G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 36: Specifications
0.50 mm OS 11.50 ~ 11.518 mm CAMSHAFT Cam height Intake 43 mm Exhaust 43 mm Journal O.D Ø28 mm Bearing oil clearance 0.02 ~ 0.061 mm End play 0.1 ~ 0.2 mm G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 37 0.2 ~ 0.6 mm 1.0 mm Over size 0.25, 0.50, 0.75, 1.00 mm 1.0 mm CONNECTING ROD Bend 0.05 mm or less Twist 0.10 mm or less Side clearance 0.100 ~ 0.250 mm 0.4 mm G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 38 Water pump type Centrifugal impeller THERMOSTAT Thermostat type Wax pellet type with jiggle valve Valve open temperature 82°C ± 1.5°C Fully open temperature 95°C WATER TEMPERATURE SENSOR Type Thermister Resistance(at 20°C) 2.31KΩ ~ 2.59KΩ G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 39: Torque Specification
Throttle body and Surge tank nut 4.3 ~ 5.5 Exhaust manifold to cylinder head bolt 1.5 ~ 2.0 Exhaust manifold cover to exhaust manifold bolt 5.0 ~ 6.0 Oxygen sensor to exhaust manifold bolt G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 40: Special Tools
(09221-32001) head bolt Valve stem oil seal installer Installation of valve stem oil seal (09222-22001) Valve spring compressor holder Removal and installation of piston and adaptor pin (Use with 09234-33003) (09222-28000, 09222-28100) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 41 Removal and installation of intake Piston pin removal and installation and exhaust valve kit (09234-33001) (Use with 09222-29000) Piston pin setting tool insert Removal and installation of piston (09234-33002) pin (Use with 09234-33001) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 42: Troubleshooting
Breakaway exhaust plate in muffler Replace Rubber hanger damaged Replace Pipe or muffler with body Interfered Repair Abnormal noise Pipe or muffler damaged Repair or replace Catalytic converter damaged Replace Each connecting gasket damaged Replace G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 43: Timing Belt System
1. Timing belt upper cover. 4. Cylinder head cover 7. Crankshaft sprocket 2. Camshaft sprocket 5. Idler 8. Timing belt lower cover 3. Timing belt 6. Tensioner 9. Flange 10. Crankshaft pulley G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 44: Removal
12. Remove the crankshaft sprocket. 13. Remove the cylinder head cover and remove camshaft sprocket. 6. Remove the crankshaft pulley. 7. Remove the crankshaft flange. 8. Remove the timing belt lower cover. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 45: Inspection
CAUTION Do not bend or twist the timing belt. Take care not to contact the timing belt with oil, water, grease and steam. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 46 8. The side of belt is severely worn out NOTE: In case of normal 9. The side of belt is cracked belt, it is cut precisely as if cut with a sharp cutter G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 47: Assembly
Crankshaft sprocket (A) → Idler pulley (B) → Idler fixing bolt 4.3 ~ 5.5kg·m Camshaft sprocket (C) → Timing belt tensioner (D). (After installing timing belt, auto tensioner may be installed) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 48 12) If the arm indicator is out of the middle of groove, loosen the bolt and repeat the above procedure. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 49: Pcv Valve
Full operating Vacuum path Clogged Vacuum path Small Engine condition Proper operating Engine condition High speed and overload PCV valve Proper operating PCV valve Light operating Vacuum path Vacuum path Very big G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 50: Service Procedure
2. Check the plunger for movement by inserting a thin stick (A) toward the valve (B) nut. 3. If the plunger is not moved, it means that PCV valve is clogging, so, clean or replace PCV valve. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 51: Intake And Exhaust System
Intake and Exhaust System Intake Manifold Components COMPONENTS MAP sensor G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 52 5. Connect the P.C.V valve hose. 6. Check connectors for connection. INSPECTION 1. Intake manifold Check each component for damage and crack. 2. Air hose Check each component for damage and crack. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 53: Exhaust Manifold
Exhaust Manifold COMPONENTS CAUTION Do not tighten parts excessively, observe the specified torque. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 54 1. Check the exhaust manifold for damage and crack. 2. Exhaust manifold gasket Check the gasket for tear or damage. INSTALLATION 1. Installation is the reverse order of removal. CAUTION Do not reuse the exhaust manifold nut. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 55: Cooling System
(3) is warm enough to make the thermostat open. When pulled back into the radiator. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 56: Testing And Adjusting
2. Check coolant level in the cooling system. 3. Look for leaks in the system. 4. Look for bent radiator fins. Be sure that air flow through the radiator does not have a restriction. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 57 3. Look at the gauge for the pressure that makes the pressure cap open. It must be as follows: A403658………76 to 100 kPa (11 to 14.5 psi) 4. If the pressure cap is bad, install a new pressure cap. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 58 Thus, in this way the degree of valve opening is varied according to the temperature of the coolant, and the temperature of the coolant is adjusted by varying the amount of coolant caused to circulate through the radiator. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 59: Cooling System Recommendation
Check the engine high idle setting. Old coolant should be drained, system cleaned and new coolant added as recommended with the commercially available automotive antifreeze. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 60 DOOSAN prefers the use of distilled water or deionized water to reduce the potential and severity of chemical insolubility.
Page 61: Coolant Pipe And Hose
CAUTION Do not apply oil or grease to the O-ring. Take care not to dirt the coolant pipe connect- ing part with sand or dust. Press-fit the coolant intake pipe completely. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 62: Water Pump
Water Pump COMPONENTS G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 63 6. Add the standard coolant. 7. Run the engine and check for leak. 1. Check each part for crack, damage, and wear and replace the water pump if necessary. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 64: Thermostat
2. Check for defect or damage. 3. Heat the thermostat as shown in the illustration and measure the valve open temperature and full open temperature. Valve open temperature Open 82°C Full open 95°C G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 65 1. Remove the fan pulley. 2. Remove the fan bracket. INSPECTION Check the bearing for damage, abnormal noise and sluggish rotation, and replace the bracket assembly if necessary. INSTALLATION Installation is the reverse order of removal. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 66: Cylinder Head Assembly
Cylinder Head Assembly Components 1. Cylinder block 4. Cylinder head bolt 2. Cylinder head gasket 5. Gasket 3. Cylinder head 6. Cylinder head cover G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 67 2. Retainer 7. Key 12. Camshaft bearing cap 3. Valve spring 8. Chain sprocket 13. Timing chain 4. Stem seal 9. Intake camshaft 14. Retainer lock 5. Spring seat 10. Camshaft sprocket G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 68 2. Using the special tool “valve spring compressor (09222-28000, 09222-28100)”, remove the retainer lock. And then, remove the spring retainer, valve spring, spring seat and valve. NOTE: Arrange parts in order disassembling not to make a mistake while reassembling. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 69 Valve margin Standard 0.03mm or less Flatness of cylinder Head gasket surface Limit 0.06mm Intake 1.15mm Standard Exhaust 1.35mm Intake 0.8mm Limit Exhaust 1.0mm G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 70 2. Using a square, measure squareness of each spring and replace it if the measured value is out of squareness excessively. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 71 Intake valve seat ring 0.6 OS 7.8 ~ 8.0 33.600 ~ 33.625 0.3 OS 7.9 ~ 8.1 28.800 ~ 28.821 Exhaust valve seat ring 0.6 OS 8.2 ~ 8.4 29.100 ~ 29.121 G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 72 5. After installing the valve guide, insert a new valve and check for perturbation. 6. When replacing the valve guide, check the valve for con-tact and correct the valve seat if necessary. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 73 2. After applying engine oil to each valve, insert the valve into the valve guide. 3. Install the spring and spring retainer. Face the enamel-plated side toward the valve spring retainer side. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 74 2.5kg·m + (60°~ 65°) + (60°~ 65°) 3.0kg·m + (60°~ 65°) + (60°~ 65°) 7. Install the camshafts. 8. Install the camshafts oil seal. 9. Install the camsprocket and timing belt. 10. Install the head cover. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 75: Lubrication System
In the cylinder head the oil is forcibly fed to the camshaft journals, rocker arm pivots and further cam surfaces. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 76: Testing And Adjusting
Start NOTE: In normal case, the recommended engine oil and operate the engine in a well ventilated area for G420F(E) engine is SAE 10W - 30. only. In an enclosed area, vent the exhaust to the outside.
Page 77 ON position. The light will turn off after the engine is started and while the engine is running, lidicating normal oil pressure. The light will G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 78: Oil Pressure Switch
NOTE: Do not tighten the oil pressure switch too normal, check for air leak. If air is leaked, replace tight. the switch because it means damage of the diaphragm. Oil pressure switch 1.3 ~ 1.5㎏∙m G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 79: Front Case And Oil Pump
Front Case and Oil Pump COMPONENTS 1. Filter 7.Relief plunger 2. Front case 8.Oil seal 3. Gasket 9.Inner rotor 4. Oil screen 10.Outer rotor 5. Plug 11.Pump cover 6.Relief spring G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 80 5. Remove the oil pan and oil screen 6. Remove the front case. 1) Remove the screws (B) from the pump housing, then separate the housing and cover (A). 2) Remove the inner (A) and outer (B) rotos. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 81 Then, install the oil pump onto the crankshaft. When the pump is in place, clean any excess grease off the crankshaft and check that the oil seal lip is not distorted. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 82 43.8mm Free height (1.724in.) Standard value 3.7kg/40.1mm Load (8.14lb/1.579in.) 3. Inspect rotor side clearance. Using a feeler gauge and precision straight edge, measure the clearance between the rotos and precision straight edge. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 83 If necessary, replace the front case. REASSEMBLY 1. Install relief plunger. Install relief plunger (A) and spring (B) into the front case hole, and install the plug(A). 39.2~49.0kgf.m Tightening torque (28.9~36.2lb-ft) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 84: Cam Shaft, Hla, Timing Chain
CAM Shaft, HLA, Timing Chain Components L4GC043A G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 85: Removal
3. Remove the ignition coil. 4. Remove the timing belt upper cover. 5. Remove the cylinder head cover. 6. Remove the tensioner. 7. Loosen the camshaft sprocket bolt and remove the cam-shaft sprocket. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 86: Inspection
5. Lightly put the camshaft on the cylinder head as shown in the illustration and after installing a dial gauge towards shaft, check the endplay. Camshaft endplay 0.1 ~ 0.2mm G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 87 Apply engine oil to the camshaft journal and cam. There a detective pin for TDC sensor in the in- take camshaft rear end and a dowel pin in the intake camshaft front end. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 88 1.4 ~ 1.5kg·m Camshaft sprocket bolt 10 ~ 12kg·m CAUTION Align the timing marks on the camshaft sprocket and the crankshaft sprocket. At this time piston no.1 cylinder should placed compression dead point. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 89 11. Assembly the ignition coil. 8. Assembly the timing belt. 12. Install the spark plug center cover. Center cover 0.25 ~ 0.35kg·m 9. Install the cylinder head cover. Apply sealant as shown in the illustration. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 90 G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 91: Crankshaft
Crankshaft Components G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 92 3. Measuring oil clearance 1) Measure O.D of the crankshaft journal and pin. 2) Measure diameter of the crankshaft bore and connecting rod bore. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 93 6. Check that the crankshaft for free rotation and the journal and pin. proper clearance between the center main bearing thrust flange and connecting rod big-end bearing. Crankshaft end-play 0.06 ~ 0.260mm G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 94 8. Install the rear oil seal case and gasket and tighten 5 bolts. When installing, apply engine oil to the oil seal round and crankshaft. 9. Install the flywheel, front case, oil pan, and timing belt train. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 95: Flywheel And Housing
Assembly 1. Install the flywheel housing and tighten the bolt to the specified torque. 2. Install the flywheel assembly and tighten the bolt to the specified torque. Flywheel bolt 12 ~ 13kg·m G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 96: Piston And Connection Rod
Piston and Connection Rod Components G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 97 And then, pull out the piston upward and measure 3) Using the press, remove the piston pin. gap using a feeler gauge. When the gap exceeds the limit, re-place the piston ring. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 98 When installing a new connecting rod, align the bearing with the notch. 2. If both end thrust surfaces of the connecting rod are damaged, partially worn, or the inside of small end is too rough, replace the connecting rod. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 99 2) With the front mark faced upward, fix the connecting rod and piston and insert it into the piston pin assembly. Front mark Piston side 0 (engraved) Connecting rod side Number (embossed) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 100 Apply enough engine oil to the piston and pis- piston ring ton ring round. Take care not to change no.1 and no.2 piston rings. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 101 5. Inspect clearance of the connecting rod big end. Clearance of connecting rod big 0.1 ~ 0.25mm 6. Install the oil screen. 7. Install the oil pan. 8. Install the cylinder head. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 102: Engine Block
Engine Block Component Tightening torque : N•m(kgf.cm , lbf•ft) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 103 Tightening torque : N•m(kgf.cm , lbf•ft) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 104 15. Remove rear oil sealcase. Remove the 5bolts (B) and rear oil sealcase (A). 16. Remove crankshaft bearing cap and check oil clearance. 8. Remove water pump. 17. Check the crankshaft end play. 9. Remove oil pan (A). G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 105 1) Using a piston ring expender, remove the 2compressionrings. 2) Remove the 2side rails and oil ring by hand. NOTE: Arrange the piston rings in the correct order only. 21. Disconnect connecting rod from piston. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 106 Clean them only 3) Remove the connecting rod cap and bearing with solvent or deter gent. half. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 107 Crankshaft pin mark location Discrimination of connecting rod bearing CLASS MARK INSIDE DIAMETER 1.514~1.517 mm BLUE (0.0596~0.0597in.) A1.511~1.514 mm BLACK (0.0595~0.0596in.) 1.508~1.511 mm NONE (0.0594~0.0595in.) 1.505~1.508 mm GREEN (0.0593~0.0594in.) 1.502~1.505mm YELLOW (0.0591~0.0593in) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 108 3) Place one strip of plastic gage across each main journal. 4) Reinstall the bearings and caps, then torque the bolts. Tightening torque : 30Nm (300kgf.cm, 22lbf.ft) + 60˚ ~ 65˚ G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 109 Use them, and the numbers or bar stamped on the JOURNAL crank (marks for main journal size), to choose the 54.956~54.962mm YELLOW Ⅰ correct bearings. (2.1636~2.1638in.) 54.950~54.956mm NONE Ⅱ (2.1633~2.1636in.) 54.944~54.950mm WHITE Ⅲ (2.1631~2.1633in.) Place of identification mark (Crankshaft bearing) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 110 Standard end play : 0.06 ~ 0.26mm (0.0023 ~ 0.010in.) Limit : 0.30 mm (0.0118in.) Main journal diameter : 55 mm (2.165in.) Crank pin diameter : 45 mm (1.77in.) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 111: Cylinder Block
NOTE: Stamp the grade mark of basic diameter with present, replace the cylinder block. rubber stamp 5. Inspect cylinder bore diameter Using a cylinder bore gauge, measure the cylinder bore diameter at position in the thrust and axial directions. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 112 4. Bore each of the cylinders to the calculated size. Standard diameter 81.97 ~ 82.00 mm(3.2272 ~ 3.2283in.) CAUTION To prevent distortion that may result from temperature rise during honing, bore cylinder holes in the firing order. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 113 If the clearance is greater than maximum, replace the piston. Piston ring end gap Standard No.1: 0.23~0.38 mm (0.0091~0.0150in.) No.2: 0.33~0.48 mm (0.0130~0.0189in.) [2.0L] Limit No.1,2,oil ring:1.0mm(0.039in.) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 114 2) Using a piston ring expander, install the 2compression rings with the code mark facing upward. 3) Position the piston rings so that the ring ends are as shown. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 115 5 lower 2) Install and uniformly tighten the 10 bearing cap bolts (A), in several passes, in the sequence bearings. shown. Tightening torque 30Nm (300kgf.cm, 22lbf.ft) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 116 4) Apply engine oil to the bolt threads. Install the 13. Install front case. rod caps with bearings, and torquethenuts: 50~53Nm(500~530kgf.cm,36.9~39lbf.ft) NOTE: Maintain downward force on The ring compressor to prevent the rings from expanding before entering the cylinder bore. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 117 Instead, reapply liquid gasket after removing the residue. After assembly, wait at least 30 minutes before filling the engine with oil. G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 118 3) Install the oil level gauge assembly (A) with the bolt. Tightening torque 12~15Nm (120~150kgf.cm, 9~11lbf.ft) 19. Install cylinder head. 19. Install timing belt. 20. Remove engine stand. 21. Install flywheel housing. 22. Install flywheel. Tightening torque 120~130Nm (1200~1300kgf.cm,89~96lbf.ft) G420F(FE) Service Manual Chapter 3. Engine Mechanical System...
Page 119: Specifications
Spark plug gap 0.7 ~ 0.8mm Starter Motor Item Specification Output 12V- 1.7 kW Pinion tooth number Alternator Item Specification Rated output 13.5V - 90A 1,000 ~ 18,000rpm Voltage regulator type Electronic, Built-in type G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 120: Ignition System
(EMI). otherwise an intermediary coil driver device must be provided. The SECM controls spark energy (dwell time) and spark discharge timing. Figure 16. Coil-On-Plug Ignition System G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 121 Service Tool. Figure 17. Ignition Coil and Extension Wire Assembly for G420F(E) Engiue G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 122 Components Circuit Diagram SECM G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 123: Inspection Of Ignition Timing
Inspection of Ignition Coil Drivers 2. Inspection (Power TR) 1) Connect the timing light. Four Power Transistors are used for G420F(E) engine. Its function is ignition coil driver, and it is 2) After inserting the clip backward the connector, located near to SECM.
Page 124: Inspection Of Ignition Coil
It is a direct connection that delivers the hottest spark possible. Resistor plugs are generally used to suppress electromagnetic interference (EMI). G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 125: Inspection Of Spark Plug
1st Coil Resistance : 0.71 ± 9 % (Ω) spark-plug mounting hole. 2. 2nd Coil Resistance measurement Measure resistance between high pressure terminals. 2nd Coil Resistance : 18∼19.5 ± 14 % (kΩ) G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 126 When installing a new sparkplug, install it after checking the uniform plug clearance. Spark plug clearance 0.7~0.8mm G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 127: Charging System
The alternator is connected to the battery through the ignition switch for alternator turn on . Therefore, alternator excitation occurs when the switch is D187478 turned on. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 128 Components G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 129: Troubleshooting
Correct or replace Loose wiring connection Retighten Short circuit Repair Battery is Fusible link cut off Replace discharged Ground fault Repair Faulty voltage regulator (Charging warning lamp illuminates) Inspect alternator Battery out Replace G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 130: Troubleshooting Procedure
Troubleshooting Procedure Inspection before Starting 1. Charging warning lamp inspection. 2. Alternator and drive belt tension inspection. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 131 3. Alternator and outer terminal connection inspection. 4. Battery outer terminal inspection. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 132 Inspection after Starting 1. Inspection of alternator charging warning lamp operation test. 2. When starting, belt slip and noise inspection 3. Inspection of battery voltage at idling (At this time charge battery only) G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 133 NOTE: When measuring output current, necessarily 7. Be sure that the hood is opened. use a slightly discharged battery. Fully charged battery is not enough to use for correct test owing to insufficient load. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 134 If voltmeter reading is 0V, it means short circuit of wire between “B” terminal and the battery (-) 6. Connect the battery ground cable. terminal, fusible link cut off or ground fault. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 135: Disassembly And Installation
4. Front cover assembly 11. Stator coil 18. Brush holder bolt 5. Front bearing 12. Rear cover 19. Slip ring guide 6. Bearing cover 13. Through bolt 20. Cover 7. Bearing cover bolt 14. Seal G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 136 3. Remove the slip ring guide (A). 4. Remove the belt by pressing inward the alternator. 5. Remove the alternator brocket. 6. Loosen the mounting and remove the alternator assembly. 7. Installation is reverse order of removal. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 137 5. Loosen 4 through bolts. 2. Inspect the rotor coil ground and check continuity between the slip ring and the core, If there is continuity, replace the rotor assembly. 6. Separate the rotor and cover. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 138 If there is both direction continuity, replace the rectifier assembly owing to short circuit of diode. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 139 2. After pressing forward the alternator, Contact the alternator front bracket with front case (A) as shown in the illustration. 3. Insert and install the nut by tightening it to the specified torque. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 140: Starting System
The pinion will stay meshed with the ring gear until the ignition switch is released. A return spring in the overrunning clutch returns the clutch to its rest position. Components G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 141: Diagnosis Procedure
20amps the start relay can easily switch this load. the solenoid is broken by releasing the ignition switch. The starting motor solenoid has two functions: 1. Engages the pinion with flywheel. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 142 Digital Multimeter or Equivalent to (5) with the multimeter while cranking or DC Clamp-On Ammeter or Equivalent attempting to crank the engine. 5. Is voltage equal to or greater than shown in Figure1? G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 143: Start Relay Tests
• If it does not crank, check for blocked engagement of the pinion and flywheel ring gear. NOTE: Blocked engagement and open solenoid contacts will give the same electrical symptoms. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 144 Start motor is rotating but Worn or broken pinion gear tooth or motor fault Repair engine is not cranking Replace flywheel ring gear Worn or broken ring gear tooth or torque converter G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 145: Starter
3. Stop ring 8. Packing B 13. Planetary gear 18. Brush holder 4. Stopper 9. Shim 14. Ball 19. Through bolt 5. Overrunning clutch 10. Internal gear 15. Packing A 20. Rear bracket G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 146: Removal And Installation
This test should be done as soon as possible not to damage the coil (in 10 seconds). 3. If the pinion is moving outward, the coil is normal, if or not, replace the magnetic switch. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 147 (in 10 seconds). 3. When releasing after pulling the pinion outward, if the pinion is returned to native position, it is normal, if or not, replace the solenoid valve. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 148 Check continuity between the commutator and the continuity, replace the armature assembly owing armature coil using a circuit tester. If there is to open circuit of commutator segment. continuity, replace the rotor assembly. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 149 2) Rotate the pinion. The pinion must be rotated clockwise but counterclockwise. 6. Brush. If the brush is worn out to the limit, replace the brush. G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 150 1) Before removing the bushing, measure the bushing press-fit depth. 2) Remove the bushing as shown in the illustration. 3) Press-fit a new bushing as the depth measured procedure 1). G420F(FE) Service Manual Chapter 4. Engine Electrical System...
Page 151: General Information
4.5 ±0.1 V APP1(Hi idle) 3.6 ±0.15 V APP2(Hi idle) 1.39 ± 0.15 V Engine Oil Pressure Actuation Pressure 0.3 +/- 0.1 kgf/cm^2 Switch Transmission Oil Actuation Temperature 125°C Temperature Switch G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 152 Power TR Operating Voltage 5-16V Ignition Coil Ass’y Coil Type Inductive Coil Supply Voltage 8-16 Vdc Primary Resistance 0.71 ohm +/- 9% Spark Plug Material Platinum spark plug Air Gap 0.7-0.8 mm G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 153 (-4.982 ± 0.498 mbar) @ 50 lbm/hr LPG) Mounting Regulator should be installed with centerline of outlet at least 15° below horizontal to permit drainage of any liquid precipitates from LPG fuel. Diaphragm should be vertically oriented. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 154 0.25 inH2O (0.623 mbar) at all airflows. Air Valve Vacuum (AVV) 1/4-28 UNF Port Size Fuel Inlet Adjustments None Idle Air Adjustment None Mounting Suitable for on-engine mounting in vertical orientation G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 155 High pressure type (built in Fuel Pump Assembly) 350 kPa (49.8 psi) Gasoline Pressure Pressure Regulator built in Fuel Pump Assembly Fuel Injector Type Electric-magnetic 14.5 +/- 0.35 ohms Coil resistance G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 156: Service Standard
0.4 ~ 0.6 2.9 ~ 4.3 Engine Coolant Temperature Sensor (ECTS) 15 ~ 20 1.5 ~ 2.0 10.8 ~ 14.5 Delivery pipe installation 19 ~ 28 1.9 ~ 2.8 13.7 ~ 20.3 G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 157: Component Location
Component Location Camshaft Position Sensor Engine Control Module (SECM48) Crankshaft Position Sensor TMAP Sensor LP Fuel Temperature Sensor Coolant Temperature Sensor G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 158 Pre-Catalyst Oxygen Sensor Electronic Throttle Body Pedal Angle Sensor Post-Catalyst Oxygen Sensor Transmission Oil Temperature Switch Engine Oil Pressure Switch G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 159 Ground speed limit switch (option) Fuel Trim Valve (FTV) Power TR Gasoline Injectors and fuel rall N-2007 LP Regulator LP Fuel Lock-off G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 160 CA100 Mixer Gasoline Fuel Pump Ass`y G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 161: G420Fe Ems (Engine Management System Overview
TMAP sensor. MI-07 is a drive-by- operating variables are compensated. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 162 MPI (multi-point injection) system is used for gasoline. The fuel type can be switched while the G420FE dual fuel engine and G420F gasoline/dual engine is stopped or running at low speeds and low fuel engine. On gasoline, the camshaft sensor along loads.
Page 163 • Sensors/Switches/Speed inputs (dual-fuel systems only) The chart below lists the MI-07 components required MI-07 System Features for a G420F (E) engine operating on LP fuel. The MI-07 system uses an advanced speed-density Q’ty DESCRIPTION control strategy for fuel, spark, and air throttle...
Page 164: Lpg Fuel System Operation
(AVV). Thus, by modulating the FTVs, the pressure regulator reference pressure can be varied between mixer inlet pressure and AVV. For a given change in the pressure regulator reference pressure, the G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 165 Stall, when the key is in the ON position but the crankshaft position sensor detects no engine revolutions; and the Run state, when the engine reaches pre-idle rpm. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 166 As the pressure of G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 167 (1) and a gas discharge jet (2). In the center of the main body is the air valve assembly, which is made up of the air valve (3), the gas-metering valve (4), and air valve diaphragm (5) G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 168 AVV causes the air valve diaphragm trained service technicians. assembly to move much farther creating a large venturi. The variable venturi air/fuel mixer constantly matches venturi size to engine demand. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 169 If the pressure on the reference side of the N-2007 secondary diaphragm is reduced, the diaphragm will close the secondary valve until a balance condition G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 170 A branch-tee fitting is installed in the atmospheric vent port of the N-2007 with one side of the branch- tee connected to the intake side of the mixer forming Figure 13. Fuel Trim Valves Connected to MI-07 System G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 171: Mpi Gasoline System Operation
MPI (multi-point injection) system is used for G420FE dual fuel engine and G420F gasoline/dual For fuel consumption reduction, engine performance fuel engine. An electric fuel pump in gasoline fuel...
Page 172: Electronic Throttle System
SECM will drive the system into one of its limp-home modes or shut the engine down, storing the appropriate fault information in the SECM. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 173: Ignition System
A topside location is best because it keeps the coils away from the heat of the exhaust. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 174: Exhaust System
SECM from properly the sensor should be evaporated. This is to avoid synchronizing, thereby preventing the engine from thermal shock of the sensor that could prematurely starting and running. fail the sensor. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 175 The reduction catalyst is the first stage of the catalytic converter. It uses platinum and rhodium to help reduce the NOx emissions. The oxidation catalyst is the second stage of the catalytic G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 176: Secm
(TPS), and the accelerator pedal the air/fuel mixture and increasing the fuel pressure position sensors (APP1 & APP2). enriches the air-fuel mixture. Control is achieved by modulating the fuel trim valves. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 177 SECM self-calibration “cross checking” compares both signals and then checks for errors. Figure 21. Peak Torque and Power Available with MI-07 System Figure 20. Throttle Position Sensor (TPS) on DV-E5 Throttle G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 178 EMI exposure throttle position sensors (TPS1 and TPS2) to the to the SECM and associated cabling. The above SECM. recommendations do not provide any guarantee of proper system performance. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 179: Secm Wiring Diagrams For G420Fe
To prevent system faults be sure to follow good wiring practices. Poor wiring cause unexpected or intermittent failures not related to MI-07 components. Figure 23. SECM Wiring Diagram for G420FE Engine Systems G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 180 Figure 23. SECM Wiring Diagram for G420FE Engine Systems G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 181: G420F Ems (Engine Management System Overview
G420F EMS (Engine Management System) Overview General Description MI-07 control system provides a complete, fully Engine speed is monitored by the SECM through a integrated engine management system for naturally Hall Effect sensor. Intake manifold air temperature aspirated engines. and absolute pressure are monitored with a TMAP sensor.
Page 182 MPI (multi-point injection) system is used for G420FE dual fuel engine and G420F gasoline/dual fuel engine. On gasoline, the camshaft sensor along with the crankshaft sensor is used to control the fuel...
Page 183 • Sensors/Switches/Speed inputs The chart below lists the MI-07 components required • Speed-load spark control with tables for dwell, for a G420F engine operating on LP fuel. timing, and fuel type • Speed-load throttle control with table for maximum TPS limiting...
Page 184: Lpg Fuel System Operation
In limp-home mode the engine speed is approximately The LP fuel filter of G420F engine is the same as 1000 rpm at no load. A variety of fault conditions can that of G420FE engine. See, “G420FE EMS initiate limp-home mode.
Page 185 (9), which is Figure 5. Heat Chamber and Coolant Passage the regulator secondary chamber, and the vapor fuel inlet of the mixer. The negative pressure in the secondary chamber causes pressure/force G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 186 When the engine is cranked over it begins to draw in air, creating a negative pressure signal. This negative pressure signal is transmitted through four vacuum ports in the air valve. Figure 7. CA100 Mixer G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 187 The variable venturi air/fuel mixer constantly matches venturi size to engine demand. Figure 12. Idle Mixture Adjustment Screw Figure 10. Bottom View of Air Valve Assembly G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 188: Mpi Gasoline System Operation
MPI Gasoline System Operation SECM The MPI Gasoline System of G420F engine is the The SECM of G420F engine is the same as that of same as that of G420FE engine. See, “MPI Gaso- G420FE engine. See, “SECM of G420FE EMS over- line System Operation of G420FE EMS overview”...
Page 189: Secm Wiring Diagrams For G420F
SECM Wiring Diagrams for G420F G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 190: Ems Inspection And Repair
• Foot Pedal Position 1&2 (FPP1 & FPP2) 0 to 5 V • Coolant Temperature Sensor (CTS) -40°F to 266°F (-40ºC to 130ºC) range, 48K ohm to 85 ohm sensor range G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 191 Low side switch, sufficient to drive a 7W incandes- cent lamp continuously • CANBus CAN 2.0b serial communication for J1939 com- munications, programming and diagnostics. Requires proper termination resistance per CAN 2.0b. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 192: Camshaft Position Sensor
Schematic Diagram • If the LED blinks, the CMPS works normally. [CIRCUIT DIAGRAM] CMPS B1 - GND B10 - CMPS SIGNAL After Main Relay A23_DRVP [HARNESS CONNECTORS] 3 2 1 CMPS G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 193: Crank Shaft Position Sensor
; hammer, wrench, bolt and nut etc.) at the CKPS's tip. 6. Rotate the steel wheel slowly and check if the LED flashes light. • If the LED blinks, the CKPS works normally. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 194: Map (Manifold Absolute Pressure) Sensor
The MAP sensor in put affects fuel delivery and ignition timing controls in the ECM. Ciruit Diagram MAP & IAT sensor Sensor Sensor power signal ground signal E C M G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 195: Iat (Intake Air Temperature)
ECM will control the necessary amount of fuel injection. Ciruit Diagram MAP & IAT sensor Sensor Sensor power signal ground signal E C M G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 196: Oxygen Sensor (Pre-Catalyst)
0.6 ~ 1.0 V. When you let the engine idle again, the voltage will fluctuate between 200 mV or lower and 0.6 ~ 1.0 V. In this case, the O2sensor can be determined as good. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 197: Oxygen Sensor (Post-Catalyst)
13.1 1,112 20.7 14..6 1,272 22.5 Schematic Diagram [CIRCUIT DIAGRAM] HO2S (B1/S2) A23 - HO2S HEATER (B1/S2) B19 - HO2S SIGNAL B1 - HO2S GND After Main Relay [HARNESS CONNECTORS] G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 198: Ect (Engine Coolant Temperature) Sensor
During cold engine operation the ECM increases the fuel injection duration and controls the ignition timing using the information of engine coolant temperature to avoid engine stalling and improve drivability. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 199 2. Install engine coolant temperature sensor and tighten it to specified torque. Tightning torque Engine coolant temperature sensor " 15~20Nm (150~200 kg.cm, 11~15 lb.ft) 3. Connect the harness connector securely. G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 200: Lp Fuel Temperature Sensor
FTS 80(176) changes according to the LP fuel temperature, the output voltage also change. 3. If the resistance deviates from the standard value greatly, replace the sensor. [Circuit Diagram] G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 201: Angle Sensor-Accelerator
2 (APP2) are sent directly to the SECM. The SECM uses a series of algorithms to self calibrate and cross check the signals from the pedal assembly. [Circuit Diagram] G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 202: Transmission Oil Temperature Switch
118°C, the switch is open again and the engine also can run. This function can protect the engine of Tier- 3 and Non cert folk lift trucks from damage as overheating. [Circuit Diagram] G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 203: Ground Speed Limit Switch (Optional)
Tier-3 and Non cert fork lift trucks is an optional feature that can be easily activated using the MotoView Service Tool. This feature may be of particular interest to customers with indoor warehouse operations. [Circuit Diagram] G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 204: Electronic Throttle Body
Sensor) TPS PIN 1(+DRIVER) ~3.0KΩ +/- engine’s current operating conditions and then TO PIN 4(-DRIVER) generates a corresponding electrical (driver) signal to the throttle-valve actuator. [Circuit Diagram] G420F(FE) Service Manual Chapter 5. Engine Management System (EMS)
Page 205: G420Fe Lp System Inspection And Repair
The regulator/converter and mixer are part of a certified system complying with EPA and CARB 2007 requirements. Only trained, certified technicians should perform disassembly, service or replacement of the regulator/ converter or mixer. G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 206: Hose Connections
Proper operation of the closed loop control greatly depends on the correct vacuum hose routing and fuel line lengths. Refer to the connection diagrams below for proper routing and maximum hose lengths when reinstalling system components. Certified System Connections Figure 26. Hose Connections for Certified Systems Diagram Notes G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 207: Removal And Installation Of
7. Remove the fuel vapor outlet hose (5) from the regulator. 8. Remove the nipple extension (6) with the lock-off from the regulator. Figure 28. N-2007 Regulator in Certified System G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 208: Removal And Installation Of Ca100 Mixer For G420Fe
(See Figure 32 for location of port barb Figure 30. CA100 Mixer in Certified System on mixer.) 1. Close the liquid outlet valve in the forklift cylinder or fuel storage container. G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 209 NOTE : A plastic O-ring spacer and an O-ring are inside the mixer/adapter assembly. Be careful not to lose these items when removing the assembly from the throttle (Figure 31). Figure 31. O-Ring and Spacer Within Mixer Adapter Assembly G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 210: Tests And Adjustments
10. Install the air cleaner hose (1). regulator/converter or mixer. Figure 32. Throttle Adapter Mount Screws G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 211: N-2007 Regulator Service Testing
(proportional to the leak size). An excessively rich air/fuel mixture can be caused by a secondary valve seat leak and the regulator should be replaced. Figure 35. Primary Stage Test Connection G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 212 NOTE : The N-2007 primary stage pressure can also be tested at idle on a running engine. The N- 2007 primary pressure should be between 40 inH20 (99.635 mbar) and 55 inH20 (136.999 mbar) at 750 rpm, idle. G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 213: Avv (Air Valve Vacuum) Testing
5. If the measured pressure drop is low, check for vacuum leaks in the manifold, throttle, mixer, TMAP sensor and attached hoses. Figure 38. KVaser Communication Adapter Figure 37. Magnehelic Gauge Connection G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 214: Idle Mixture Adjustment
1.2 kW. b) Attach the engine to a dynamometer. Attach the Mototune Service Tool to the wiring harness and add parameter MAFPort to the display screen. G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 215 FTV duty cycle reading is within the optimum range (35-55%) and engine rpm is stable. DO NOT adjust the screw so far outward that the tamper proof cap cannot be installed. A duty cycle G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 216 55%). Place your thumb over the adjustment port for a more accurate reading by preventing air from leaking past the mixture adjustment screw, which may cause the duty cycle to decrease. G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 217: Parts Description
Fuel Inlet Air Horn Gasket Air Horn Adapter 2-1/16” (52.37mm) Fillister Head Screws SEMS Lockwasher 10-24 UNC x 5/8” Throttle Body Gasket Fillister Head Screws SEMS Split Lockwasher #12-24 x 5/8” G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 218 Exploded View of CA100 Mixer (Certified) Figure 44. CA100 Certified Mixer Exploded View G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 219 Fillister Head Screws SEMS Split Lockwasher #12-24 x 1-3/8” Hex Head Screws SEMS Split Lockwasher 1/4-20 x 5/8” Plug, Socket Head Pipe (T-086) Cover, Secondary Diaphragm Lockwasher, Int. Tooth (T-210) #8 SST Torx Screws (T-15) #8-32 x 5/8” G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 220 Exploded View of N-2007 Regulator (Certified) Figure 46. N-2007 Certified Regulator Exploded View G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 221: G420F Lpg System Inspection And Repair
G420F LPG System Inspection and Repair Removal and Installation WARNING – PROPER USE • LP gas is highly flammable. To prevent perso- nal injury, keep fire and flammable materials away from the lift truck when work is done on the fuel system.
Page 222: G420F Fuel System Connections
G420F Fuel System Connections Figure 27. Hose Connections for Non-Certified Systems DIAGRAM NOTES Only one 90 fitting permissible on vapor fuel line between mixer and regulator  Vapor fuel fittings (regulator and mixer) must have minimum ID of 0.46” (11.68mm)
Page 223: Removal And Installation Of N-2001 Lp Regulator/Converter
6. Remove the fuel vapor outlet hose (5) from the regulator. Figure 29. N-2001 Regulator in Non-Certified System G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 224: Removal And Installation Of Ca100 Mixer For G420F
4. Apollo Adapter-ITB, Mixer 12. Remove the vapor fuel inlet fitting from the 5. ITB 6. O-Ring Spacer mixer. 7. O-Ring 8. Bolt-ITB.Conn 9. Gasket-ITB 10. Bolt Figure 33. CA100 Mixer in Non-Certified System G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 225 7. Install the vacuum line (2) to the mixer. 8. Install the air cleaner hose (1). Figure 31. O-Ring and Spacer Within Mixer Adapter Assembly Figure 32. Throttle Adapter Mount Screws G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 226: Tests And Adjustments
Figure 30. Secondary Stage Test Connection 3. Union Tee 1/4” NPT with three 1/4” NPT x 1/4” hose barb 4. Vacuum hose 5. 0-3” WC Magnehelic gauge (inches of water column) G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 227 NOTE : The N-2001 primary stage pressure can also be tested at idle on a running engine. The N- 2001 primary pressure should be between 40 inH20 (99.635 mbar) and 55 inH20 (136.999 mbar) at 750 rpm, idle. G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 228: Avv (Air Valve Vacuum) Testing
Figure 38. KVaser Communication Adapter Figure 37. Magnehelic Gauge Connection Ignition Timing Adjustment Figure 39. Crypt Token Installed on Laptop With the MI-07 system, ignition-timing advance is controlled by the SECM. G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 229: Idle Mixture Adjustment
G420F LP Fuel Systems With O2 Sensor 3. Monitor the output of the UEGO or HEGO sensor while the engine is at the higher speed with the Idle Adjustment load applied (phi = 1.00 to 1.05 is optimal).
Page 230 3. Once the power valve is set, bring the engine back to idle and verify the idle screw setting. Figure 43. Main Mixture Adjustment on Bottom of Mixer (partial view) G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 231: Parts Description
Parts Description CA100 Mixer for G420F Engine Refer to Figure 45 exploded view on facing page. REF NO. DESCRIPTION Screws 10-24 x 5/8” SEMS Mixer Cover Air Valve Spring Screws 6-32 x 1/4” SEMS Plate Backup Diaphragm, Silicone Air Valve Ring Air Valve Assembly Idle Screw 3/8-16 x 1-1/4”...
Page 232 Exploded View CA100 Mixer Figure 45. CA100 Non-Certified Mixer Exploded View G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 233 (1) BODY (2) VALVE (3) SPRING (4) COVER (5) WASHER (6) SCREW (7) GASKET (8) ADAPTER (9) SCREW (10)GASKET (11) SCREW Figure M6 3. Remove the air-valve assembly from the mixer as shown in (Figure M6). G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 234 Now reinstall the air-valve spring and diaphragm cover (Figure M8). Figure M9 6. Tighten the cover fastners and reinstall the mixer on the engine (Figure M9). G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 235 N-2001 Regulator for G420F Engine Refer to Figure 47 exploded view on facing page. Parts List N-2001-RSA Regulator REF NO. DESCRIPTION Cover Screws 8-32 x 5/8” SEMS Torx Screws (T-15) 8-32 x 5/8” Tamper Resistant Lockwasher #8 Internal Tooth Secondary Cover Secondary Diaphragm Assembly Pan Head Screw 10-24 x 1/4”...
Page 236 Exploded View N-2001-RSA Regulator Figure 47. N-2001 Regulator Exploded View G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 237 2. Remove the six primary diaphragm cover screws (4) and the primary cover assembly (5). Figure R6 Remove the primary diaphragm by sliding the diaphragm to one side, releasing the primary valve pin (Figure R6). G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 238 (7), the primary valve (8) and the primary valve o-ring seal (9). The primary valve goes through the inlet plate, then through the body assembly and is retained by the primary diaphragm (Figure R9). G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 239 4. Clean the regulator body (casting) with a parts cleaning solvent. Be sure to remove all seals and gaskets before cleaning the casting with solvent. Figure R11 5. Make sure all parts (Figure R11) are completely dry before re-assembly. G420F(FE) Service Manual Chapter 6. LPG FUEL DELIVERY SYSTEM...
Page 240: Specification
09353-38000 delivery pipe and fuel feed Fuel Pressure Gage Adapter line Connection between Fuel Pressure Gage (09353- 09353-24000 24100) and Fuel Pressure Fuel Pressure Gage Connector Gage Adapter (09353- 38000) G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 241: Components Location
Components Location 1. Fuel Tank 2. Fuel Pump (Including full pressure regulator and fuel filter) 3. Fuel Hose Assy 4. Fuel Rail 5. Injector G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 242: Fuel Pressure Test
Adapter (09353-38000). 4. Connect the Fuel Pressure Gage and Hose (09353-24100) to Fuel Pressure Gage Connector (09353-24000). 5. Connect the fuel feed hose to the Fuel Pressure Gage Adapter (09353-38000). G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 243 5. Stop the engine and check for a change in the fuel pressure gauge reading. After engine stops, the gage reading should hold for about 5 minutes G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 244: Injector
With fuel pressure applied, check that there is no fuel leakage from the fuel pressure gauge or connection part. 3. If the vehicle is normal, connect the fuel pump connector. G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 245 (℃) (℉) (℃) (℉) 12.2 ~ 12.3 16.6 ~ 16.8 13.3 ~ 13.5 17.7 ~ 17.9 14.4 ~ 14.6 18.8 ~ 19.0 15.5 ~ 15.7 19.9 ~ 20.1 Schematic diagram G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 246: Injector Inspection
2. Remove the delivery pipe with the fuel injectors. CAUTION Be careful not to drop any injectors when removing the delivery pipe. Be aware that fuel may flow out when removing the injector. G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 247 2. Apply a coating of solvent, spindle oil or gasoline to the O-ring of the injector. 3. While turning the injector to the left and right, fit it on to the delivery pipe. G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 248: Fuel Pump
Cover the hose connection with a shop towel to prevent splashing of fuel caused by residual pressure in the fuel line. 3. Unfasten the fuel pump cap (D) counter clock wise. G420F(FE) Service Manual Chapter 7. MPI Gasoune Fuel Delivery System...
Page 249: Preliminary Checks
This signals the operator that a fault has been troubleshooting and save valuable time. detected by the SECM. 2. Determine that there are no diagnostic codes stored, or there is a diagnostic code but no MIL light. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 250: Basic Troubleshooting Guide
Engine operation □ Driving □ Constant speed □ Acceleration □ Deceleration □ Other_____________________________ 4. MIL/DTC MIL (Malfunction Indicator Lamp) □ Remains ON □ Sometimes lights up □ Does not light □ Normal □ DTC(_______________________________________) G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 251: Basic Inspection Procedure
(Radios, fans, lights, for poor connections, loose wires, bent, broken or etc.). corroded pins, and then verify that the connectors are always securely fastened. 3. Slightly shake the connector and wiring harness vertically and horizontally. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 252: Connector Inspection Procedure
NOTE: Use a fine wire to prevent damage to the or pull locking lever. terminal. Do not damage the terminal when inserting the tater lead. 3. Listen for a click when locking connectors. This sound indicates that they are securely locked. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 253 1. Clean the contact points using air gun and/or shop rag. NOTE: Never uses and paper when polishing the contact points, otherwise the contact point may be damaged. 2. In case of abnormal contact pressure, replace the female terminal. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 254 (A) and (C) as shown in [FIG.2]. In [FIG.2.] the measured resistance of line1and 2 is higher than 1㏁ and below 1Ω respectively. Specifically the open circuit is line 1(Line 2 is G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 255 1Ω and higher than 1㏁ respectively. Specifically the short to ground circuit is line 1 (Line 2is normal). To find exact broken point, check the sub line of line1 as described in the following step. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 256: Symptom Troubleshooting Guide Chart
Symptom Troubleshooting Guide Chart for MPI Gasoline Engine Engine Is Not Starting Engine Is Difficult To Start(Cranking OK) G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 257 Irregular Idling Or Engine Is Suddenly Stopped G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 258 Engine Hesitation Or Insuffient Accelelation G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 259 G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 260 Troubleshooting Guide for MPI Gasoline Engine • The following number represents inspection order. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 261 G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 262: Basic Troubleshooting
(4) If the wiring and connectors check OK, and a diagnostic code was stored for a circuit having a sensor, check sensor. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 263: Surges And/Or Stumbles
(*) Refer to Table 1 for description of gaseous and liquid O2 adapts. Related MIL Faults: Pre-catalyst O2 sensor errors / O2 control errors Dither valve DC faults / EST faults / ETC faults G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 264: Engine Cranking But Will Not Start / Difficult To Start
See Chapter 6 Tests and Adjustments. Incorrect air/fuel or ignition/spark See Chapter 8 Advanced Diagnostics. control Verify the crankshaft position signal is present No crankshaft position sensor signal See Chapter 8 Advanced Diagnostics. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 265 • Pickup coil resistance and connections* (*) Where present Related MIL Faults: ETC spring check / ETC faults / EST faults / TPS conflict APP faults / Encoder error / MAP faults Injector faults / Oil pressure faults G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 266: Speed Performance / Hesitation During Acceleration
Check spark advance for excessive retarded ignition timing. Use Service Tool. Check secondary voltage using an oscilloscope or a spark tester to check for a Ignition system malfunction weak coil. Check spark plug condition. Check poor spark plug primary and secondary wire condition. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 267 Engine mechanical Check engine valve timing and compression Check engine for correct or worn camshaft. Related MIL Faults: EST faults ETC faults ETC spring check TPS faults APP faults Encoder error Delayed Shutdown faults G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 268: Detonation / Spark Knock
Check combustion chambers for excessive carbon build up. Check combustion chamber pressure by performing a compression test. Check for incorrect basic engine parts such as cam, heads, pistons, etc. Related MIL Faults: EST faults Encoder error High coolant temperature faults G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 269: Backfire
Fuel lock off valve Make sure lock off valve is closing properly. Ignition system malfunction Check spark advance at idle. Related MIL Faults: EST faults / ETC faults / Pre-catalyst O2 sensor faults G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 270: Rough, Unstable, Incorrect Idle, Or Stalling
Valve should snap back. If not, replace Component malfunction valve. Check alternator output voltage. Repair if less than 9 or more than 16 volts. Perform a cylinder compression check. Engine mechanical See Chapter 3 Engine Mechanical System. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 271 • Between mixer and throttle body Vacuum leak • Between throttle body and intake manifold • Between intake manifold and cylinder head Related MIL Faults: EST faults ETC Sticking fault Pre-catalyst adapts error G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 272: Cuts Out, Misses
Check base engine. Remove rocker covers and check for bent pushrods, worn rocker arms, broken valve springs, worn camshaft lobes, and valve timing. Repair as necessary. Related MIL Faults: EST faults ETC Sticking fault G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 273: Poor Fuel Economy / Excessive Fuel Consumption Lpg Exhaust Smell
Refer to Chapter 3 Engine Mechanical System. Related MIL Faults: Pre-catalyst O2 sensor faults / Low side driver / Dither valve duty cycle EST faults / Fuel adapt faults / Low coolant temperature G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 274: High Idle Speed
Check for vacuum hose leak. Engine mechanical Check for PCV malfunction. Check for defective intake gasket. Related MIL Faults: ETC Sticking fault Idle adapt out of range MAP Sticking fault MAP high value G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 275: Excessive Exhaust Emissions Or Odors
Follow instructions on label. Check for plugged PCV valve. Check for stuck or blocked PCV hose. Check for fuel in the crankcase. Related MIL Faults: Low side driver Fuel adapt faults EST faults G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 276: Diagnostic Aids For Rich / Lean Operation
LP (Trim valve duty cycle<10%) • Check for vacuum leaks, replace hoses, o-rings, and gaskets as necessary • Check balance line for blockage, replace as necessary • Check vapor hose for restrictions, replace as necessary G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 277: Chart T-1 Restricted Exhaust System Check
2. Increase engine speed to 2000 rpm and observe gage. Reading should not exceed 3 psig (20.68 kPa). 3. If the backpressure at either speed exceeds specification, a restricted exhaust system is indicated. G420F(FE) Service Manual Chapter 8. Basic Troubleshooting...
Page 278: Displaying Fault Codes (Dfc) From Secm Memory
(3) times within five (5) seconds to enable the display codes feature of the SECM. Simply turn the key OFF to exit display mode. The code list will continue to repeat until the key is turned OFF. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 279: Fault Action Descriptions
Pre-catalyst O2 sensor is disabled. Disable Liquid O2 Control: In Gasoline mode, closed loop correction of air fuel ratio based on the Pre-catalyst O2 sensor is disabled. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 280: Table 1. Fault List Definitions
APP1 signal has shorted to power or the ground for the (61) sensor has opened APP1 sensor voltage out of range low, normally set if the APP2AdaptHiMax APP1 signal has shorted to ground, circuit has opened or (68) sensor has failed G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 281 (16) the engine overheating. Engine Coolant Temperature Sensor Input is High. Normally ECTRangeHigh set if coolant sensor wire has been disconnected or circuit (15) has opened to the SECM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 282 EST6_Open spark module EST6 output shorted high or low, EST6 signal shorted to EST6_Short ground or power or defective spark module EST7 output open, possibly open EST7 signal or defective EST7_Open spark module G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 283 Fuel Temperature Sensor Input is High. Normally set if the fuel FuelTempRangeHigh temperature sensor wire has been disconnected or the circuit has opened to the SECM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 284 Possible causes for this fault are sensor disconnected, sensor heater failed, sensor element failed, heater relay, or SECM control of heater relay is disconnected or failed. Reserved for Future Use G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 285 Gasoline Injector 8 open circuit, broken injector 8 wire or Inj8Open defective injector Cold Start Valve Fault, signal has opened or shorted to LSDFault_CSValve ground or power or defective cold start valve G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 286 LiqPostO2FailedLean sensor to not be properly heated. If any Pre O2 sensor faults are set, diagnose these first and after correcting these faults recheck if this fault sets. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 287 Post-catalyst O2 sensor voltage out of range high, sensor O2_PostCatRangeHigh signal shorted to voltage source (5V or battery) Post -catalyst O2 sensor voltage out of range low, sensor O2_PostCatRangeLow signal shorted to ground SensVoltRangeHigh Sensor reference voltage XDRP too high (56) G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 288 Learned closed throttle end of TPS2 sensor range lower than TPS2AdaptLoMin expected TPS2 sensor voltage out of range high, normally set if the TPS2RangeHigh TPS2 signal has shorted to power or ground for the sensor has opened G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 289 TPS sensors differ by more than expected amount. TPS_Sensors_Conflict NOTE: The TPS is not a serviceable item and can only be repaired by replacing the DV-EV throttle assembly TransOilTemp Excessive transmission oil temperature G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 290: Dfc Probable Fault Action
SECM (Signal) Pin B15 to ECT Pin 3 or open circuit (3) CheckEngineLight SECM (Sensor GND) Pin B1 to ECT Pin 1 (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 291 Pin 2 Switched 12V to Crank connection on the crankshaft sensor Pin 1 Check for defective Crank sensor sensor (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 292 Learned WOT end of TPS2 sensor None range higher than expected TPS1AdaptHiMin Learned WOT end of TPS1 sensor None range lower than expected (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 293 TMAP Pin 1(GND) to Pin 4 (pressure signal KPA) (2.4kΩ - 8.2kΩ) TMAP Pin 3 (power) to Pin 4 (pressure signal KPA) (3.4k Ω- 8.2kΩ) (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 294 TMAP connector and chassis ground or the sensor measure the IAT resistance has failed. Resistance is approx 2400 ohms at room temperature. (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 295: Output Open, Possibly Open Est5 Signal Or Defective
(of both connectors) spark module Verify +12 Vdc on ignition module Pin B (of both connectors) Refer to application manual for specific engine details. (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 296: Refer To Application Manual For Specific
Vdc on ignition module Pin B (of both spark module connectors) Refer to application manual for specific engine details. (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 297: N/A
EST6_Short EST6 output shorted high or low, EST6 signal shorted None ground or power or defective spark module (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 298 NOTE: The throttle assembly is not a serviceable item and can only be repaired by replacing the DV-EV throttle assembly. (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 299 (with key on) SECM Pin A23 (DRVP) to SECM Pin A16 (DRVG) SECM Pin A23 (DRVP) to SECM Pin B17 (DRVG) (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 300 APP1 signal has shorted to (2) CheckEngineLight Check APP1 signal at SECM PIN B7 ground, circuit has opened or sensor has failed (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 301 APP1 signal at SECM Pin B7 defective pedal • Cycle the pedal several times and assembly check APP2 signal at SECM Pin B16 (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 302 In LPG mode, system had to TurnOnMil trim valves, e.g. leaking valve or hose (72) adapt rich more than Check for missing orifice(s). expected (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 303 Check for vacuum leaks Check for indicates extended lean (2) DisableGasPost O2Ctrl leaks in exhaust, catalytic converter, operation on LPG HEGO sensors; repair leaks. Check all sensor connections (see fault 742 corrective actions). G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 304 Verify O2 sensor heater circuit is O2 sensor operating measuring heater resistance (2.1Ω ± 0.4 Ω) O2 Pin 2 (HEATER GND) to Pin 1 (HEATER PWR) (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 305 Look for leaks in exhaust, catalytic operation on gasoline converter, HEGO sensors; repair leaks. Check all sensor connections (see fault 842 corrective actions). (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 306 SECM (sensor GND) Pin B1 to FTS has been disconnected Pin 2 or the circuit has opened to the SECM. (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 307 TurnOnMil reached—replace HEGO Replace Post-catalyst HEGO sensor sensors ServiceFault5 Service Interval 5 has been TurnOnMil Replace engine timing belt reached—replace timing belt (*) Fault actions shown are default values specified by the OEM. G420F(FE) Service Manual Chapter 9. Advanced Diagnostics...
Page 308: Service Tool Software (Motoview)
Service tool software (MotoView) and Extension cable. A334071 Extension Cable (L=200 cm) A334082 Extension Cable (L=20 cm) A343079 USB (Universal Serial Bus) to CAN (Controller Area Network) Converter Assembly A343080 Service Tool Software (includes CD and Crypt Token (License Dongle)) G420F(FE) Service Manual Appendix...
Page 309: Service Tool Connection To Secm
Communications to the SECM from the Service Tool is through a CAN port using a two wire connection. High-speed CAN reaches 1Mbps and is used for engine control and power-train applications. Laptop Computer Running Service Tool Software G420F(FE) Service Manual Appendix...
Page 310: Service Tool Display
Fault Screen, Ground speed select option, Fault list and Override screen. Service Screen Key parameters of a running engine are grouped together for easy reference in the ENGINE block. Throttle and Foot Pedal parameters are displayed together in the CNTRL Block G420F(FE) Service Manual Appendix...
Page 311 Fault records are recorded as FIFO (First In First Out) Once a fault is recorded a repeat of the same fault will not be written to the history list Flash Codes begin at record 1 not record 10 G420F(FE) Service Manual Appendix...
Page 312 Ground Speed Select Option Speed Limits are set by entering RPM values in the red boxes Values are restricted by Upper and Lower Limits G420F(FE) Service Manual Appendix...
Page 313 A FAULT LIST screen provides a complete list of faults including Fault Codes with monitored parameters so the technician does not have to refer to the manual for fault descriptions or codes while using the service tool. G420F(FE) Service Manual Appendix...
Page 314 3. Click the Override Select box for the component 4. Select “Pass-Through” for normal operation or “Override” to manually control the component. WARNING Be aware of fuel flow and ignition during manual mode or engine damage may result. G420F(FE) Service Manual Appendix...
Page 315: Secm Field Update With Service Tool
Copy the field update file (.mfu) to the C:/ECUF Files/Updates directory, corresponding (.dll) file C:/ECU Files/TDBDLL. Copy the .dll file to the TDDBLL directory Copy the .mfu update file to the Updates directory G420F(FE) Service Manual Appendix...
Page 316 USB ports). STEP 3 - LAUNCH THE MOTOUPDATE APPLICATION Launch the MotoUpdate application. You will see a Welcome scree. Select “SECM-1” in the location field, then select Next G420F(FE) Service Manual Appendix...
Page 317 No Upgrader Available for this Engine This calibration ID has one (1) available upgrade No Upgrader Available for this Engine Selecting the “Details” button on the pervious screen will bring up the Upgrade Details screen G420F(FE) Service Manual Appendix...
Page 318 If option of upgrading another module. If another repeatedly unsuccessful, please contact . module is to be upgraded, select the “Upgrade again” button and select next. If another upgrade is not required, select finish. G420F(FE) Service Manual Appendix...
Page 319: Ground Speed Limits (Option)
Ground Speed Limits (Option) The maximum allowable speed of Doosan forklifts is an optional feature that can be easily activated using the MotoView service tool. This feature is very useful customers with indoor warehouse operations. Here’s how you can activate the speed-limiting feature.
Page 320 With pushing of inching pedal, the maximum RPM for normal speed governing (Neutral State) is set at 2600. With release of inching pedal, the maximum RPM for limited speed governing (In-Gear State) is set at 2000. G420F(FE) Service Manual Appendix...
Page 321: Lpg And Lpg Fuel Tanks
242 deg. F / 117 deg. C, which will cause the carbon build up. water to remain in liquid state at the engines operating temperature. G420F(FE) Service Manual Appendix...
Page 322: Lpg Fuel Tanks
(4) Service Valve (Tank end male coupling) (5) Filler Valve (6) Alignment Pin (7) Vapor Withdrawal Tube (Only used with Vapor Withdrawal) (8) 80% Limiter Tube (9) Liquid Withdrawal Tube (10) Foot Ring (11) Fuel Level Float (12) Collar G420F(FE) Service Manual Appendix...
Page 323 In addition to possibly starving the engine for fuel, a partly open valve may restrict the flow enough to prevent the excess flow valve from closing in the event of a ruptured fuel line. G420F(FE) Service Manual Appendix...
Page 324 The extra washer or o-ring must be removed from the shaft and the Figure 9 coupling reconnected. Figure 8 G420F(FE) Service Manual Appendix...
Page 325: Regulatory Compliance
SECM-48 input power must be supplied from a power supply/battery charger certified to IEC standard with a SELV (Safety Extra Low Voltage) classified output. SECM-48 inputs outputs only connected to other circuits certified as SELV (Safety Extra Low Voltage). G420F(FE) Service Manual Appendix...
Page 326: Abbreviations
Relative fuel-air ratio or percent of stoichiometric fuel (actual fuel-air ratio / stoichiometric fuel-air ratio) Revolutions per minute Small engine control module SECM Temperature and manifold absolute pressure TMAP Throttle position sensor Voltage of direct current type Volumetric efficiency Wide open throttle G420F(FE) Service Manual Appendix...

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Doosan G420F Service Manual

Chapter 1. General Information

Precautions before Service

Tightening Torque

Recommended Lubricants and Capacities

Engine Model and Engine Serial Number

General Specification

Engine Power and Torque

Chapter 2 . RECOMMENDED

General Maintenance

Cooling System Maintenance

Fuel System Maintenance

Maintenance Schedule

Chapter 5 . ENGINE MANAGEMENT

General Information

Chapter 3 . ENGINE MECHANICAL

Special Tools

Timing Belt System

PCV Valve

Intake and Exhaust System

Cylinder Head Assembly

Lubrication System

CAM Shaft, HLA, Timing Chain

Crankshaft

Flywheel and Housing

Piston and Connection Rod

Cylinder Block

Charging System

Starting System

Chapter 4 . ENGINE ELECTRICAL

Ignition System

EMS Inspection and Repair

Chapter 6 . LPG FUEL DELIVERY

G420FE LP System Inspection and Repair

G420F LPG System Inspection and Repair

Chapter 7 . MPI GASOLINE FUEL

Specification

Components Location

Fuel Pressure Test

Injector

Injector Inspection

Fuel Pump

Chapter 8. Basic Troubleshooting

Preliminary Checks

Basic Troubleshooting Guide

Basic Troubleshooting

Chapter 9. Advanced Diagnostics

Reading Diagnostic Fault Codes

Clearing Fault (Dfc) Codes

Fault Action Descriptions

Fault List Definitions

Dfc Probable Fault Action

Appendix Service Tool Software (Motoview)

Ground Speed Limits (Option)

LPG and LPG Fuel Tanks

Regulatory Compliance

Special Conditions for Safe Use

Abbreviations

Quick Links

Troubleshooting

Need help?

Questions and answers

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Summary of Contents for Doosan G420F