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 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. than what is intended by Hyundai SeasAll. REFUELING...
INSTALLATION & OPERATION MANUAL U125 Series Engines ENGINE BREAK-IN INITIAL BREAK-IN PROCEDURE The first 20 hours of operation is the 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.
INSTALLATION & OPERATION MANUAL U125 Series Engines ENGINE SUSPENSION EYES • 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 •...
INSTALLATION & OPERATION MANUAL U125 Series Engines 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...
INSTALLATION & OPERATION MANUAL U125 Series Engines ENGINE DIMENSIONS Bobtail Front view Side view [for sterndrive] Side view [for shaftdrive] Side view [for shaftdrive] Side view [for waterjet with bearing housing] Side view [for waterjet with bearing housing] -12-...
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INSTALLATION & OPERATION MANUAL U125 Series Engines MerCruiser Bravo One X Diesel Side view Front view ZF 25 A ZF 25 A Front view Side view -13-...
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INSTALLATION & OPERATION MANUAL U125 Series Engines ZF 45 A Side view Front view ZF 45 C ZF 45 C Side view Front view -14-...
ENGINE MOUNT DIMENSIONS CAUTION CAUTION USE ONLY THE ORIGINAL HYUNDAI SEASALL ENGINE MOUNTS THAT USE ONLY THE ORIGINAL HYUNDAI SEASALL ENGINE MOUNTS THAT WERE SUPPLIED WITH THE INITIAL PURCHASE WERE SUPPLIED WITH THE INITIAL PURCHASE WERE SUPPLIED WITH THE INITIAL PURCHASE.
MODELS PLEASE SEE THE SEPARATE BOOKLETS INCLUDED IN THE MODELS, PLEASE SEE THE SEPARATE BOOKLETS INCLUDED IN THE MODELS, PLEASE SEE THE SEPARATE BOOKLETS INCLUDED IN THE ORIGINAL PACKAGING OF YOUR HYUNDAI SEASALL PURCHASE. ORIGINAL PACKAGING OF YOUR HYUNDAI SEASALL PURCHASE. -16-...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 3 CHAPTER 3 ENGINE OPERATION STARTING ENGINE STOPPING ENGINE • Before starting the engine, you should • The should be run for a few minutes at idle check engine oil, coolant, gearbox oil, fuel ( in neutral ) before turning it off.
INSTALLATION & OPERATION MANUAL U125 Series Engines 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 SEAWATER FLOW – OPEN COOLING CIRCUIT Water strainer ← Water valve ← Water pickup ↓ ① Seawater pump ↓ ② I t ② Intercooler ↓ ③ Transmission oil cooler ↓ ④ Heat exchanger ↓...
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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 th filt t fl h it th with clean water or compressed air. •...
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INSTALLATION & OPERATION MANUAL U125 Series Engines CHECKING SEAWATER 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. •...
INSTALLATION & OPERATION MANUAL U125 Series Engines 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 and then open the cap of the expansion tank carefully.
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 5 CHAPTER 5 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 possible thanks to the quick response of the solenoid type injector.
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 Hi h ③ High pressure pump ↓ ④ Common rail ↓...
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.
CAUTION CAUTION HYUNDAI SEASALL’S GUARANTEES OR WARRANTIES ARE VOID IN HYUNDAI SEASALL’S GUARANTEES OR WARRANTIES ARE VOID IN CASES WHERE DAMAGE TO FUEL INJECTON COMPONENTS (HIGH CASES WHERE DAMAGE TO FUEL INJECTON COMPONENTS (HIGH PRESSURE PUMP, INJECTORS, ETC.) CAN BE ATTRIBUTED TO THE...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 6 CHAPTER 6 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 &...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHECK AIRFILTER • The original Hyundai SeasAll air cleaner may be cleaned and reused. • If the air filter is very dirty, it can reduce flow of air to the engine This can result in reduced air to the engine.
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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 7 CHAPTER 7 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.
AND SOURCES OF IGNITION. IF YOU HAVE A USED OIL DISPOSAL PROBLEM, PLEASE HAVE THE ENGINE OIL CHANGED BY YOUR PROBLEM, PLEASE HAVE THE ENGINE OIL CHANGED BY YOUR NEAREST HYUNDAI SEASALL SERVICE DEALER. NEAREST HYUNDAI SEASALL SERVICE DEALER. -35-...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 8 CHAPTER 8 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. And it should be at least 50㎟...
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 LOAD TEST • Perform the following steps to complete the load Voltage Temperature test procedure for maintenance-free batteries.
• 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 ECM(ECU) Power : 20Amp...
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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 Plug 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 CHAPTER 9 INSTRUMENT SYSTEM INSTRUMENT CONNECTIONS Gauges only available for dual EOI application ※ For information about the installation and operation of the EOI (Engine Operating Indicator) system, please refer to Chapter 10. -40-...
INSTALLATION & OPERATION MANUAL U125 Series Engines STANDARD INSTRUMENTS Ø 5 RPM Gauge Coolant Temperature Gauge Battery Voltmeter Gauge Ignition Key switch NOTE: Gauge panel (show above) is not standard but available as an option COOLANT TEMPERATURE GAUGE • This gauge will work when the key is in the “ON”...
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INSTALLATION & OPERATION MANUAL U125 Series Engines RPM GAUGE 1) When the key is at ignition ON position, this gauge will work. 2) This gauge indicates real-time engine rpm. 3) Avoid max. rpm and WOT (Wide Open Throttle) before a cold engine is fully warmed up, as it can harm the engine.
INSTALLATION & OPERATION MANUAL U125 Series Engines BATTERY VOLT METER GAUGE • This gauge will work when the key is in the “ON” position. • This gauge indicates real-time battery voltage. • If battery voltage is not sufficient, the engine can not be started.
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 10 CHAPTER 10 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.
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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) 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 Not used CN5 (VOLT GAUGE) Ignition power Ground Illumination...
INSTALLATION & OPERATION MANUAL U125 Series Engines CN8 (KEY BOX) 1. Ignition power 2. Starter power 3. Permanent power NEUTRAL SWITCH AND DUAL EOI CONNECTION 1) Neutral switch wires should be connected at pin #4 and #5 of the external connector of the EOI.
INSTALLATION & OPERATION MANUAL U125 Series Engines TRIM WIRING CONNECTION DIAGRAM (STERNDRIVES ONLY) TRIM WIRING CONNECTION DIAGRAM (STERNDRIVES ONLY) TRIM LIMITE TRIM SENDER TRIM PUMP TRIM PUMP REMOTE CONTROL TRANSOM PLATE TRAILER SWITCH (SIDE TYPE ONLY) GEAR LUBE MONITOR GAUGE-TRIM BATTERY GAUGE-VOLT E O I...
(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.
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INSTALLATION & OPERATION MANUAL U125 Series Engines FULL DTC(DIAGNOSIS TROUBLE CODE) LIST P code DESCRIPTION P0016 Crankshaft Position – Camshaft Position Correlation P0047 Turbocharger Boost Control Solenoid Circuit Low P0048 Turbocharger Boost Control Solenoid Circuit High P0069 Manifold Absolute Pressure – Barometric Pressure Correlation P0087 Fuel Rail/System Pressure - Too Low P0088...
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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 P0604 Internal Control Module Random Access Memory (RAM) Error...
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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 P2138 Throttle/Pedal Position Sensor/Switch “D” / “E” Voltage Correlation 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 11 CHAPTER 11 ANTI CORROSION SYSTEM Heat exchanger Sacrificial anodes A sacrificial anode must be replaced when more than 60% of it has been used. Check especially frequently when used in saltwater. It is recommended to replace the sacrificial anodes at the start of each season.
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 12 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 CHAPTER 13 CHAPTER 13 MAINTENANCE PREDELIVERY INSPECTION CHECK LIST BEFORE THE WATER TEST ON THE WATER TEST Boat drain plug in place Seawater inlet valve open (check before putting boat in water) Engine coolant level Seawater pump operation Cooling system hose clamps tight Seawater strainer correctly mounted...
INSTALLATION & OPERATION MANUAL H380 Series MAINTENANCE SCHEDULE Whichever comes first Maintenance Maintenance intervals 200h / 400h / Daily Daily item 1year 2years Check the coolant level and for leaks ● Replace the seawater pump impeller ● Cooling system Inspect the thermostat ●...
INSTALLATION & OPERATION MANUAL U125 Series Engines CHAPTER 14 CHAPTER 14 TROUBLESHOOTING GUIDE ■ Starter motor does not crank the engine Possible Causes •Engine stop switch ON position Engine stop switch “ON” position •Engine is not shifted to neutral position Engine is not shifted to neutral position •Safety Stop Switch activated •Wrong neutral switch connection to EOI...
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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 ■...
CHAPTER 15 WARRANTY WHAT IS COVERED Hyundai SeasAll warrants its new products to be free of defects in material and workmanship during the period described below. DURATION OF COVERAGE This Limited Warranty provides coverage for two (2) years from the date the product is first sold to a recreational use retail purchaser or when the Product has been operated for 1000 hours, whichever occurs first.
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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 Warranty coverage becomes available upon proper registration of the product by documented.
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• Use of other than Hyundai SeasAll genuine replacement parts when making warranty repairs. • Participating in or preparing for racing or other competitive activity.
Text, figures and standards in this guide are based on information current at the time of printing. Reprinting, reproduction or translation, in whole or in part, is not permitted without the written approval of HYUNDAI SEASALL. All rights according to the applicable copyright laws are expressly reserved for HYUNDAI SEASALL. Subject to alterations.
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