Isuzu 6HK1X Engine

⚠ Adjust valve clearance carefully so that the bridge may become level (hit the end of the 2 valve axes).

⚠ If the bridge adjusting screw is poorly adjusted, the bridge may tilt, be pushed down and seize, damaging the bridge guide.

Tools: 0.4 mm thickness gauge, flathead screwdriver

1. Loosen all bridge and rocker arm adjusting nuts and screws (4HK1: 8 nuts/8 screws, 6HK1: 12 nuts/12 screws).
2. Place a 0.4 mm thickness gauge between the No.1 cylinder rocker arm end and bridge cap.
3. Tighten rocker arm adjusting screw until the gauge is snug between rocker arm end and bridge cap.
4. Tighten the rocker arm lock nut.
5. Tighten the bridge adjusting screw until the bridge contacts the valve head.
6. Tighten the bridge lock nut.
7. Check the thickness gauge is still held snugly; if too tight loosen bridge screw and nut.
8. Remove the thickness gauge and repeat for remaining cylinders.

⚠ ALWAYS wear safety glasses when removing or installing force fitted parts.

Tools: Jack stands, Screwdriver or standard adjusting tool

1. Place the trailer on jack stands on secure level ground.
2. Check the wheel and drum for free rotation.
3. Remove the adjusting hole cover from the adjusting slot at bottom brake backing plate.
4. With a screwdriver or standard adjusting tool, rotate star wheel to expand brake shoes.
5. Adjust shoes outward until lining against drum makes wheel difficult to turn.
6. Rotate star wheel in opposite direction until wheel rotates freely with slight lining drag.
7. Replace the adjusting hole cover and lower trailer to the ground.
8. Repeat steps on remaining brakes.

⚠ Adjust while cold.

⚠ Ensure bridge is level and hits both valve axis ends.

⚠ Avoid seizing bridge guide.

Tools: 0.4 mm thickness gauge, wrenches, screwdriver

1. Remove cylinder head cover and fuel injector harness ASM.
2. Remove leak off pipe and rotate crankshaft to No.1 cylinder compression TDC.
3. Insert 0.4 mm thickness gauge between rocker arm and bridge to check clearance.
4. Loosen all bridge and rocker arm adjusting nuts and screws (4HK1: 8 nuts/8 screws; 6HK1: 12 nuts/12 screws).
5. Place 0.4 mm thickness gauge between No.1 cylinder rocker arm end and bridge cap.
6. Tighten rocker arm adjusting screw until gauge is snug, then tighten lock nut.
7. Tighten bridge adjusting screw until bridge contacts valve head, then tighten lock nut.
8. Check gauge snugness; adjust if too tight.
9. Remove gauge and repeat for remaining cylinders.

⚠ Clear ECM memory after measurement because DTC is recorded when harness connector is removed.

Tools: Compression gauge 5-8840-2675-0 (J-26999-12), Compression gauge adapter EN-46722 (4HK1), Compression gauge adapter 5-8840-2622-0 (6HK1)

1. Warm up engine.
2. Remove negative battery terminal and all glow plugs.
3. Disconnect fuel injector harness connector (no fuel injected).
4. Install compression gauge adapter and gauge (4HK1: EN-46722; 6HK1: 5-8840-2622-0; gauge: 5-8840-2675-0/J-26999-12).
5. Turn starter and measure each cylinder; keep engine speed at 200 rpm or more.
6. Remove gauge, reconnect harness, install glow plugs, reconnect battery.

⚠ NEVER place jumper plates on the voltage change-over board while generator is in operation.

1. Jumper the voltage change-over board for 240V operation.
2. Connect the load wires to the UVWO terminals.
3. Turn the voltage regulator knob clockwise to increase, counterclockwise to decrease voltage output.

⚠ ALWAYS make sure connections to the UVWO terminals are secure and tight; arcing could cause a fire.

1. Jumper the voltage change-over board for 480V operation using 6 jumper plates in 3 positions.
2. Every jumper plate must be used.
3. Connect the load wires to the UVWO terminals.

⚠ ALWAYS disconnect the negative terminal FIRST and reconnect negative terminal LAST.

⚠ Incorrect battery cable connection will cause electrical damage.

1. NEVER connect battery cables when MPEC Control Switch is in MANUAL position; set to OFF/RESET.
2. Place a small amount of battery terminal treatment compound around both terminals.
3. Red cable to positive terminal, black cable to negative terminal.

⚠ Allow engine to cool when flushing out radiator. Flushing while hot could cause serious burns from water or steam.

1. Open both cocks at crankcase side and lower radiator and drain coolant.
2. Open radiator cap while draining. Remove overflow tank and drain.
3. Check hoses for softening and kinks; check clamps for leakage.
4. Tighten both cocks and replace overflow tank.
5. Replace with coolant as recommended by engine manufacturer.
6. Close radiator cap tightly.
7. Flush radiator by running clean tap water until rust and dirt removed.

1. Drain the fuel tank completely; treat with fuel stabilizer if necessary.
2. Completely drain oil from crankcase and refill with fresh oil.
3. Clean entire generator, internal and external.
4. Cover the generating set and store in a clean, dry place.
5. Disconnect the battery.
6. Make sure engine coolant is at proper level.
7. If mounted on a trailer, jack trailer up and place on blocks.

⚠ Adjust while being cold.

Tools: 0.4 mm thickness gauge

1. Remove the cylinder head cover.
2. Remove the fuel injector harness ASM by loosening the terminal nuts alternately.
3. Remove the leak off pipe.
4. Rotate the crankshaft so No.1 cylinder is at compression TDC.
5. Insert a 0.4 mm thickness gauge between rocker arm and bridge to check clearance.

⚠ Diesel fuel and its vapors are dangerous to health; avoid skin contact and inhaling fumes.

⚠ DO NOT OVERFILL fuel system; leave room for fuel expansion.

⚠ NEVER smoke around or near the generator.

1. Level tanks - make sure fuel cells are level with the ground.
2. Open cabinet doors on the right side of the generator.
3. Remove fuel cap and fill tank.
4. NEVER overfill fuel tank; read fuel gauge when filling.

⚠ DO NOT spill the fuel during disassembly.

1. Replace the fuel filter cartridge with new one every 500 hours or so.
2. Loosen the drain plug at the lower top of the fuel filter.
3. Drain fuel in fuel body together with the mixed water.
4. Vent any air.