This engine installation and operation manual is provided as guidance for the installation of Hyundai SeasAll engine in a boat, and to describe engine operation. Its purpose is to provide technical information to aid in performing an effective engine installation so as to achieve both maximum performance and service life.
Wait until the engine is fully cool to do inspection and maintenance. • Do not use the engine for a purpose other than what is intended by Hyundai SeasAll. REFUELING Do not modify the performance of the...
INSTALLATION & OPERATION MANUAL U125 Series Engines APPROXIMATE CONVERSIONS FROM STANDARD MULTIPLY MULTIPLY SYMBOL SYMBOL SYMBOL SYMBOL 0.039 inch inch 25.4 LENGTH inch LENGTH inch 2.54 3.28 0.3048 0.0016 645.2 AREA AREA 10.764 0.093 in ³ 0.061 in³ 16.388 0.06 61.023 in³...
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INSTALLATION & OPERATION MANUAL U125 Series Engines 2.ENGINE SUSPENSION • To lift the engine, first remove the engine cover. You will find two engine eyes (see figure) • To avoid engine damage, take care that engine lift chains or belts do not hit or touch surrounding parts during engine lifting.
INSTALLATION & OPERATION MANUAL U125 Series Engines 3.ENGINE IDENTIFICATION Engine identification is affixed to the engine block and the ECU box (see figure). SERIAL NUMBER ON THE ENGINE BLOCK • ENGINE NAME PLATE...
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INSTALLATION & OPERATION MANUAL U125 Series Engines 4.SCHEMATIC DIAGRAM OF COMMON RAIL DIESEL ENGINE...
INSTALLATION & OPERATION MANUAL U125 Series Engines 7.BELT LAYOUT & ENGINE DIMENSIONS V-RIBBED BELT LAYOUT Bobtail Front view Side view [for sterndrive] Side view [for shaftdrive] Side view [for waterjet with bearing housing] -13-...
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INSTALLATION & OPERATION MANUAL U125 Series Engines MerCruiser Bravo One X Diesel Side view Front view ZF 25 A Front view Side view -14-...
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INSTALLATION & OPERATION MANUAL U125 Series Engines ZF 45 A Side view Front view ZF 45 C Side view Front view -15-...
2.ENGINE MOUNT DIMENSIONS CAUTION USE ONLY THE ORIGINAL HYUNDAI SEASALL ENGINE MOUNTS THAT WERE SUPPLIED WITH THE INITIAL PURCHASE. AFTER INSTALLATION AND ALIGNMENT OF THE ENGINE, MAKE SURE THAT NO RESIDUAL TENSION EXISTS IN THE DRIVETRAIN.
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FOR INFORMATION ON INSTALLATION OF THE STERNDRIVE BRAVO MODELS, PLEASE SEE THE SEPARATE BOOKLETS INCLUDED IN THE ORIGINAL PACKAGING OF YOUR HYUNDAI SEASALL PURCHASE. HYUNDAI SEASALL ENGINES MUST BE USE THE GENUINE ALIGNMENT TOOL OF HYUNDAI SEASALL OTHER THE DRIVE COUPLER WILL BE DAMAGED. -17-...
INSTALLATION & OPERATION MANUAL U125 Series Engines 2.SEAWATER FLOW – OPEN COOLING CIRCUIT Water strainer ← Water valve ← Water pickup ↓ ① Seawater pump ↓ ② Intercooler ↓ ③ Transmission oil cooler ↓ ④ Heat exchanger ↓ ⑤ Exhaust elbow ↓...
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INSTALLATION & OPERATION MANUAL U125 Series Engines CLEAN STRAINER FILTER • Stop the engine and close the water valve. • Remove the filter cap. • Remove the filter element, flush it thoroughly with clean water or compressed air. • Insert the cleaned filter element and screw on the filter cap.
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INSTALLATION & OPERATION MANUAL U125 Series Engines CHECKING SEA WATER PUMP & IMPELLER • Stop the engine and close the water valve. • Remove the impeller housing cover. • Remove the impeller from inside the seawater pump. • Check the condition of impeller and bushing. •...
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INSTALLATION & OPERATION MANUAL U125 Series Engines 2.4 SEA WATER DRAIN HEAT EXCHANGER • Remove anode, then please let the sea water drain. • Removing and Inspection procedure 1. Remove the anode plugs on the heat exchanger (A) and the intercooler (B). 2.
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INSTALLATION & OPERATION MANUAL U125 Series Engines 3.ENGINE COOLANT FLOW THERMOSTAT CLOSED ① Engine coolant outlet ② Engine oil cooler ③ Exhaust manifold ④ Engine coolant inlet THERMOSTAT OPENED ① Engine coolant outlet ② Engine oil cooler Thermostat opened (opening temp 85℃) ③...
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INSTALLATION & OPERATION MANUAL U125 Series Engines • If the coolant level is low, add enough specified coolant to provide protection against freezing and corrosion. Bring the level to MAX, but do not overfill. • If frequent additions are required, see an authorized dealer for a cooling system inspection.
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INSTALLATION & OPERATION MANUAL U125 Series Engines REMOVING AIR BUBBLES IN COOLANT • Start the engine and warm it up at a low rpm. • Stop the engine and allow the engine to cool, and then open the cap of the expansion tank carefully.
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U125 Series Engines EXHAUST SYSTEM • Your Hyundai SeasAll engine’s exhaust system consists of a coolant-cooled exhaust manifold and a seawater-cooled exhaust elbow (water injected wet exhaust system). • The vessel’s exhaust line should not be made too long and should be as straight as possible.
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 4 FUEL SYSTEM The fuel supply system of this engine is diesel common rail direct injection. In order to optimize engine combustion, maximum injection pressure is up to 1600 bar. Multi-injection is possible thanks to the quick response of the solenoid type injector.
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INSTALLATION & OPERATION MANUAL U125 Series Engines FUEL FLOW Fuel tank ↓ Auxiliary fuel filter ↓ ① Fuel filter (low pressure) ↓ ② Fuel filter with water detection sensor ↓ ③ High pressure pump ↓ ④ Common rail ↓ ⑤ Injector or return to fuel tank LOW PRESSURE FUEL LINE ①...
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INSTALLATION & OPERATION MANUAL U125 Series Engines ACCELERATION SENSOR AND CONTROL LEVER When installing control lever cable to acceleration 65 mm sensor, be sure that the acceleration sensor lever is fully released at the idle position and fully pulled to the full-load position. The swing distance of the lever between idle and full-load position is 65mm.
③ After starting the engine, check to make certain the fuel filter warning light is off. CAUTION HYUNDAI SEASALL’S GUARANTEES OR WARRANTIES ARE VOID IN CASES WHERE DAMAGE TO FUEL INJECTON COMPONENTS (HIGH PRESSURE PUMP, INJECTORS, ETC.) CAN BE ATTRIBUTED TO THE USE OF UNQUALIFIED FUELS.
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 5 AIR INTAKE SYSTEM The intake air system of this engine is optimized by VGT and a highly efficient intercooler system. The pressure of the air system is up to about abs. 2.5 bar in order to optimize engine combustion. filter Boost pressure &...
U125 Series Engines AIR FILTER MAINTENANCE • The original Hyundai SeasAll air cleaner may be cleaned and reused. • If the air filter is very dirty, it can increase airflow resistance and reduce flow of air to the engine. This can result in reduced power and fuel efficiency.
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 6 LUBRICATION SYSTEM ENGINE OIL LEVEL CHECKS The engine oil level must be checked at regular intervals. • Be sure the boat is level. • Start the engine and allow it to reach normal operating temperature.
WARNING USED OIL MUST BE STORED IN A SAFE PLACE AWAY FROM CHILDREN AND SOURCES OF IGNITION. IF YOU HAVE A USED OIL DISPOSAL PROBLEM, PLEASE HAVE THE ENGINE OIL CHANGED BY YOUR NEAREST HYUNDAI SEASALL SERVICE DEALER. -34-...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 7 ELECTRICAL SYSTEM BATTERY CABLE CONNECTIONS • The size of battery cable should be at least 40㎟ within a length of 4m. • And it should be at least 50㎟ if the cable is longer than 4m. •...
INSTALLATION & OPERATION MANUAL U125 Series Engines BATTERY CHECKS Battery inspection is very important in electronically controlled engines: You must check the battery condition regularly. LOAD TEST • Perform the following steps to complete the load Voltage Temperature test procedure for maintenance-free batteries. °...
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• If the replacement fuse blows, this indicates an electrical problem. Avoid using the system involved immediately consult authorized Hyundai SeasAll dealer. Fuses in the ECU Box System Power : 30Amp Ignition Power : 5Amp ECM(ECU) Power : 20Amp Main Relay Power : 15Amp...
INSTALLATION & OPERATION MANUAL U125 Series Engines RELAYS Relays in the ECU Box 1) Oil Extraction Pump Relay : 30Amp 2) Main Relay : 30Amp 3) Starter Solenoid Relay : 30Amp 4) Glow Relay : 70Amp Using an ohmmeter, check that there is continuity between each terminal. Terminal Continuity 30 - 87...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 9 EOI SYSTEM The Engine Operating Indicator (EOI) system gives you a lot of information about the engine’s current status. You can hear alarm beeps, or see information including RPM, coolant temperature, warning lamps, error codes and engine working time. If the switch is on, warning lamps for battery, engine oil and so on will flash.
INSTALLATION & OPERATION MANUAL U125 Series Engines SWITCHES • Buzzer Reset Switch - This switch is used for turning off the alarm temporarily. • Dimmer Switch - This switch is used for controlling brightness of the other gauges connected to the EOI. •...
INSTALLATION & OPERATION MANUAL U125 Series Engines EOI PIN ASSIGNMENT CN1 (MAIN EOI CONNECTOR FROM ENGINE) 1. Ignition power 13. RPM signal 2. Main relay power 14. Spare 3. Permanent power 15. Spare 4. Not used 16. Spare 5. Not used 17.
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INSTALLATION & OPERATION MANUAL U125 Series Engines CN3 (TACHOMETER) Main relay power RPM signal Ground Illumination Illumination CAN_H CAN_L Not used CN4 (COOLANT TEMP. GAUGE) Coolant temperature signal Ignition power Ground Illumination Illumination Not used CN5 (VOLT GAUGE) Ignition power Ground Illumination Illumination...
INSTALLATION & OPERATION MANUAL U125 Series Engines TRIM WIRING CONNECTION DIAGRAM (STERNDRIVES ONLY) TRIM LIMITE TRIM SENDER TRIM PUMP REMOTE CONTROL TRANSOM PLATE TRAILER SWITCH (SIDE TYPE ONLY) GEAR LUBE MONITOR GAUGE-TRIM BATTERY GAUGE-VOLT E O I GAUGE & LAMP POWER BUZZER (DRIVE OIL) - 49 -...
INSTALLATION & OPERATION MANUAL U125 Series Engines G-SCAN G-scan is diagnosis tool have function the DTC analysis, fault code searching, data analysis and ECU upgrade. G-SCAN CONNECTIONS G-scan can be connected to the CN6 connector of EOI, as well as G-scan connector in the ECU box.
(diagnosis trouble code) will give you information about it. The DTC display is only for initial assistance and to aid communication with a Hyundai SeasAll dealer if there is an emergency. You should contact your nearest Hyundai SeasAll dealer as soon as possible if a system problem arises.
INSTALLATION & OPERATION MANUAL U125 Series Engines FULL DTC(DIAGNOSIS TROUBLE CODE) LIST P code DESCRIPTION Crankshaft Position – Camshaft Position Correlation P0016 P0047 Turbocharger Boost Control Solenoid Circuit Low P0048 Turbocharger Boost Control Solenoid Circuit High Manifold Absolute Pressure – Barometric Pressure Correlation P0069 P0087 Fuel Rail/System Pressure - Too Low...
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INSTALLATION & OPERATION MANUAL U125 Series Engines P code DESCRIPTION P0232 Fuel Pump Secondary Circuit High P0234 Turbocharger Over boost Condition P0237 Turbocharger Boost Sensor "A" Circuit Low P0238 Turbocharger Boost Sensor "A" Circuit High P0252 Injection Pump Fuel Metering Control "A" Range/Performance P0253 Injection Pump Fuel Metering Control "A"...
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INSTALLATION & OPERATION MANUAL U125 Series Engines P code DESCRIPTION P0341 Camshaft Position Sensor A Circuit Range/Performance P0381 Glow Plug/Heater Indicator Circuit P0562 System Voltage Low P0563 System Voltage High P0601 Internal Control Module Memory Check Sum Error P0602 Control Module Programming Error P0604 Internal Control Module Random Access Memory (RAM) Error P0605...
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INSTALLATION & OPERATION MANUAL U125 Series Engines P code DESCRIPTION P1171 Minimum Rail Pressure Exceeded P1172 Maximum Rail Pressure Exceeded P1173 Set Value of PCV not in Plausibility Range P1185 Maximum Pressure Exceeded P1186 Minimum Pressure at Engine Speed Too Low P1187 Regulator Valve Stick P1188...
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INSTALLATION & OPERATION MANUAL U125 Series Engines P code DESCRIPTION Throttle/Pedal Position Sensor/Switch “D” / “E” Voltage Correlation P2138 P2299 Brake Pedal Position / Accelerator Pedal Position Incompatible P2228 Manifold Absolute Pressure/Barometric Pressure Circuit Low Input P2229 Manifold Absolute Pressure/Barometric Pressure Circuit High Input P2262 Turbocharger Boost Pressure Not Detected - Mechanical P2263...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 10 ANTI CORROSION SYSTEM Heat exchanger Sacrificial anodes 1) Sacrificial anode must be replace every 250hr The sacrificial anode check especially frequently when used in saltwater. It is recommended to replace the sacrificial anode at the start of each season. CAUTION •...
INSTALLATION & OPERATION MANUAL U125 Series Engines 2. ENGINE BREAK-IN Initial Break-in Procedure The first 20 hours of operation is the engine break-in period. During this period, it is important that the engine is operated as outlined below. 1) DO NOT operate engine at idle rpm for extended periods of time during the first 10 hours.
INSTALLATION & OPERATION MANUAL U125 Series Engines 3.EMERGENCY STOP • You can stop the engine by pushing this button. After releasing the switch by twisting the button, you can start the engine again. (Normally, the button should be in the “out” position.) •...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 12 ENGINE STORAGE The major consideration in preparing your engine for storage is to protect it from rust, corrosion, and damage caused by freezing of trapped water. The following storage procedures should be followed to prepare your engine for out-of-season storage or prolonged storage (two months or longer and/or winter storage) : CHECK LIST •...
INSTALLATION & OPERATION MANUAL U125 Series Engines WINTER STORAGE Protect your engine from freezing and corrosion damage by following the procedures indicated below. •LUBRICATION SYSTEM • COOLING SYSTEM -. IF the seawater system is not filled with an -. Start the engine and allow it to reach normal antifreeze solution as per the instructions above, operating temperature.
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 13 MAINTENANCE 1. THE INITIAL RUNNING CHECK - BEFORE THE WATER TEST - ON THE WATER TEST Seawater inlet valve open Boat drain plug in place (Check before putting boat in water) Engine coolant level Seawater pump operation Cooling system hose clamps tight...
INSTALLATION & OPERATION MANUAL U125 Series Engines 2.MAINTENANCE SCHEDULE ○ : Check/Clean, ◇ : Check ( Replace if necessary), ● : Replace Which ever comes first Interval Every Every 250 Every 500 Every 1,000 1,500 Daily Hours Hours Hours Hours / 1 years / 2 years / 4 years...
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INSTALLATION & OPERATION MANUAL U125 Series Engines 3. STERNDRIVE & TRANSMISSION MAINTENANCE SCHEDULE Whichever comes first Maintenance intervals Maintenance 100h / Daily item 1year ● Check sterndrive unit oil level (Transmission) ● Trim pump oil level ● Steering fluid level ●...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 14 TROUBLESHOOTING GUIDE ■ Starter motor does not crank the engine Possible Causes •Engine stop switch “ON” position •Engine is not shifted to neutral position •Safety Stop Switch activated •Wrong neutral switch connection to EOI •Weak battery or battery connections are loose •Starter motor solenoid or slave solenoid failure or corroded...
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INSTALLATION & OPERATION MANUAL U125 Series Engines ■ Engine rattling, noisy engine Possible Causes •Compensation of individual injector not •No engine coolant temperature sensor signal adapted •Low compression pressure •Clogged injector return line •No rail pressure sensor signal •Faulty injector •Poor injector O-ring •Carbon deposit on the injector ■...
Warranty coverage is available only to retail customers who purchase from a dealer authorized by Hyundai SeasAll to distribute the product in the country in which the sale occurred, and then only after the Hyundai SeasAll specified pre-delivery inspection process is completed and documented.
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• Cylinder Liner or Cylinder Bore scratches are not included in extended major part warranty coverage. Hyundai SeasAll Rating Categories For Marine Auxiliary Engine (Ratings in accordance with ISO 8528 ) Standby Power 1) Operating less than 500 hours per year with average 90% load of the declared Standby Power 2) No overload capability is available for this rating.
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SeasAll will verify the warranty registration of the new owner. WHAT HYUNDAI SEASALL WILL DO Hyundai SeasAll will pay for all parts and labor needed to repair the damage to the product resulting from a defect in materials or factory workmanship.
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U125 Series Engines OWNER’S OBLIGATIONS It is the owner’s obligation to install, operate, maintain and care for Hyundai SeasAll engines in accordance with the instructions and requirements stated in the Installation and Operation Manual. The owner is responsible for providing enough time and cooperation to get the engine repaired by an authorized dealer, and to deliver it to a proper facility for repair.
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Transmissions and drive systems (ZF Marine, Mercury etc.) are covered under separate warranties, provided and serviced by those companies. For information on those warranties, please see the separate booklets included in the original packaging of your Hyundai SeasAll purchase. - 75 -...
WARRANTY REGISTRATION CARD Date of sale This card is essential for registration of the customer’s warranty. Month Year Please fill out the following registration card in English. If Warranty Transfer , Check box ■OWNER’S INFORMATION Name or Company E-Mail Address Country State / Province / City Operating Location...