John Deere 6.8L OEM Diesel PSS Operator's Manual
![John Deere 6.8L OEM Diesel PSS Engine manual cover](/images/prPHCGXgCjhCDUidZYZVpGXR/thumbs/thumb175x175.webp)
The recommended oil type for the John Deere 6.8L OEM Diesel PSS Engine is a high-quality diesel engine oil meeting API CJ-4 specifications.
It is recommended to change the engine oil every 250 hours of operation or at least once a year, whichever comes first.
To bleed the fuel system, turn the ignition on, open the bleed screw on the fuel filter, and use the manual priming pump until fuel free of air bubbles flows from the bleed screw. Tighten the screw afterward.
Check for coolant levels, ensure the radiator is clean and unobstructed, verify the water pump operation, and inspect the thermostat and cooling fan for proper functionality.
Use a 50/50 mix of ethylene glycol-based antifreeze and distilled water, ensuring it meets John Deere's cool-gard specifications.
Remove the fuel injectors, insert the compression gauge into each cylinder, crank the engine, and record the pressure readings. Compare them to the manufacturer’s specifications for consistency.
Signs include excessive exhaust smoke, loss of power, unusual noises from the turbo, and increased oil consumption.
Drain the fuel system, change the oil, remove the battery, and store the engine in a dry, covered area. Use engine storage fogging oil in the cylinders to prevent rust.
The correct valve clearance is typically intake: 0.015 inches and exhaust: 0.018 inches, but always check the engine’s service manual for specific settings.
Regular maintenance, including timely oil changes, proper air filter maintenance, and ensuring the fuel system is clean, can help maintain optimal fuel efficiency.