John Deere 6068HFG82 Engine

Tools: Torque wrench, Long-handled 1/2 inch drive tool

1. Release belt tension using long-handled 1/2 inch drive tool; remove belt from pulleys.
2. Release tension on tensioner arm and remove drive tool.
3. Put a mark on the swing arm of the tensioner.
4. Measure 21 mm (0.83 in.) from the mark and put a second mark on the tensioner mounting base.
5. Install torque wrench in square hole aligned with roller and tensioner centre.
6. Rotate swing arm with torque wrench until marks are aligned.
7. Record torque measurement and compare with specification.
8. Replace tensioner assembly as required.

Tools: JDE83 or JDG820 Flywheel Turning Tool, Timing pin JDG1571, Feeler gauge, Screwdriver and wrench

1. Remove rocker arm cover and crankcase vent tube.
2. Rotate flywheel until No. 1 piston is at TDC compression stroke; insert timing pin.
3. Check and adjust valve clearance to specification.
4. Loosen locknut on rocker arm adjusting screw; turn screw until feeler gauge slips with slight drag.
5. Hold adjusting screw and tighten locknut to 27 N·m (20 lb.-ft.).
6. Recheck clearance after tightening locknut.
7. Rotate flywheel 360 degrees and adjust remaining valves per firing order.
8. Reinstall rocker arm cover and crankcase vent tube.

⚠ High-pressure fluid remaining in fuel lines can cause serious injury; do not disconnect HPCR lines.

Tools: Two open-end wrenches

1. Loosen air bleed screw two full turns.
2. Operate fuel pump primer lever until fuel flow is free from air bubbles.
3. Tighten bleed screw securely; continue operating primer until pumping action is not felt.
4. Start engine and check for leaks.
5. If needed, loosen fuel return line at injection pump and prime until bubble-free; tighten.
6. At injection nozzles, loosen line and crank engine until bubble-free fuel flows; retighten to 27 N·m (20 lb.-ft.).
7. Repeat for remaining injection nozzles.
8. If engine still will not start, contact authorized servicing dealer.

⚠ DO NOT overtighten oil filter.

Tools: Suitable filter wrench, Clean rag

1. Run engine approximately 5 minutes to warm oil; shut off.
2. Open oil pan drain valve and drain crankcase oil while warm.
3. Remove and discard oil filter element using a filter wrench.
4. Apply clean engine oil to inner and outer seals and filter threads.
5. Wipe sealing surfaces; install filter by hand until tight against dust seal.
6. Close oil pan drain valve.
7. Fill crankcase with correct John Deere engine oil; do not overfill.
8. Start engine, check for leaks; stop and check oil level after 10 minutes.

⚠ Do not dump old fuel into the new filter element.

1. Clean fuel filter assembly and surrounding area.
2. Disconnect water-in-fuel sensor wiring.
3. Loosen drain plug and drain fuel into a suitable container.
4. Grasp retaining ring and rotate clockwise 1/3 turn; remove ring and element.
5. Inspect filter mounting base; clean as required.
6. Install new filter element dry, properly indexed and seated.
7. Install retaining ring with dust seal in place; hand tighten until it snaps.
8. Bleed the fuel system.

⚠ Never reinstall an air filter showing evidence of bad condition.

Tools: Compressed air supply

1. Thoroughly clean all dirt around air filter area.
2. Unlatch and remove air filter cover.
3. Remove air filter element from canister; clean all dirt from inside canister.
4. Clean air filter element with compressed air from clean to dirty side.
5. Mark air filter to keep track of each cleaning operation.
6. Depress air restriction indicator reset button and release to reset.
7. Replace element after six cleanings or at least once a year.
8. Check air system entirely for proper condition.

⚠ Explosive release of fluid from pressurized cooling system can cause serious burns; only remove filler cap when cool.

1. Slowly open the radiator cap.
2. Remove oil cooler housing drain plug and open radiator drain valve; drain all coolant.
3. Close all drain orifices after coolant has drained.
4. Fill with clean water, run engine until water passes through thermostat, then drain.
5. Fill with cleaning product such as PMCC2610 or PMCC2638 and follow label directions.
6. Drain cleaner, fill with water, flush, run and drain again.
7. Check cooling system hoses; replace as necessary.
8. Close orifices, fill with specified coolant; loosen temperature sensor or plug to vent air.

Tools: Breaker bar and socket

1. Inspect belts for cracks, fraying or stretched areas; replace if necessary.
2. Release belt tension (automatic tensioner: breaker bar on tension arm; manual: loosen alternator cap screws).
3. Remove poly-V belt from pulleys and discard.
4. Install new belt, ensuring it is correctly seated in all pulley grooves.
5. Apply tension to belt per Check Belt section.
6. Start engine and check belt alignment.

Tools: D05104ST tester

1. Remove radiator cap and attach to D05104ST tester.
2. Pressurize cap to specification; gauge should hold pressure 10 seconds within normal range.
3. If gauge does not hold, replace radiator cap.
4. Remove cap from gauge, turn 180 degrees and retest to confirm.
5. Allow engine to cool, carefully remove radiator cap and fill to normal operating level.
6. Connect gauge and adapter to radiator filler neck and pressurize system.
7. Check all hose connections, radiator and engine for leaks.
8. Correct leaks and retest system pressure.

⚠ Do not remove the cap from a HOT engine radiator.

1. Check engine oil level: add as required.
2. Check engine coolant level: add as required.
3. Drain water from fuel filter: clean or replace element as required.
4. Service air cleaner if restriction indicator shows red.
5. Fill fuel tank with clean diesel.
6. Keep battery terminals clean and lightly greased.
7. Check engine belts and hoses for fit and damage.
8. Check air vents/grilles and inspect for leaks or arcing.

⚠ Do NOT use engine starting fluids.

⚠ Allow starter to cool one minute between start attempts.

1. Verify all external electrical power loads are OFF.
2. Verify main breaker is OFF.
3. Verify battery disconnect switch is ON.
4. Reset (pull to unlatch) Emergency Stop Button.
5. Push controller START button.
6. Wait for preheating if enabled.
7. Allow engine to warm up 3 to 5 minutes.
8. Check control panel for proper voltages and no red diagnostic lamps.

1. Turn off all external electrical power loads.
2. Turn main breaker OFF.
3. Allow 5 minute cool down.
4. Push controller STOP button.
5. Wait at least 15 seconds before restarting.
6. Fill fuel tank at end of working day to prevent condensate.