Kohler KD425-2 Workshop Manual

The recommended oil type for the Kohler KD425-2 engine is SAE 10W-30, which provides optimal performance across a wide temperature range.
The air filter should be checked every 50 hours of operation and replaced every 200 hours or as needed, depending on operating conditions.
To start a cold Kohler KD425-2 engine, ensure the fuel shut-off valve is open, set the throttle to half, and pull the recoil starter firmly.
Check the fuel level, ensure the spark plug is clean and properly connected, verify the air filter is not clogged, and make sure the oil level is adequate.
To change the oil, warm up the engine, turn it off, remove the oil drain plug, drain the old oil, replace the drain plug, and fill with new oil to the appropriate level.
Ensure the cooling fins are clean and unobstructed, use the correct oil type, and operate the engine within its recommended load limits.
Check and replace if necessary the air filter, ensure the oil level is not too high, and verify that the fuel is clean and fresh.
Adjust the carburetor by turning the idle mixture screw and the idle speed screw until the engine runs smoothly at idle. Consult the manual for specific settings.
After long-term storage, change the oil, inspect the fuel system for leaks, check the spark plug, and clean or replace the air filter before starting the engine.
Inspect the spark plug every 100 hours and clean or replace it every 300 hours of operation to ensure optimal engine performance.