Cub Cadet 3654, 3660 service manual Removing the cap to prevent dirt from contaminating the oil

rest of the hydraulic system. Fill the replacement filter with a good grade of 20W-50 oil and lubricate the sealing surface. Screw the filter onto the filter base until it seats and then another one-half turn to seal.

Note: Always wipe off the hydraulic tank fill cap and the area around it before

removing the cap to prevent dirt from contaminating the oil.

Remove the fill cap and fill the tank with the same 20W-50 oil selected for the filter until the oil level is up to the level of the second hole in the fill tube. Leave this air space for expansion. Start the engine and let it run at idle for about five minutes. Check the filter for leaks. Idling the engine and the pumps in this way will purge any air from the system. Shut off the engine and recheck the oil level in the tank. Top-off if necessary until the oil level is up to the second hole n the fill tube.

3.Hydrostatic Transmissions and motors: The pumps are the hardest-working components in the hydraulic system. They are in operation all the time the engine is running. Because of extremely close tolerances, wear is an important factor in their life. Contami- nants in the hydraulic oil and cavitation does the greatest harm to the pumps. Cavitation is a blockage in the supply lines that pro- duces a partial vacuum causing violent bubbling in the hydraulic oil in the pump.

Check the two suction hoses (the hoses connected to the filter) daily before starting the engine. Look for a flattened condition or any leaks and repair or replace as necessary. A flattened or leakng suction hose will permit cavitation to develop which can destroy the pumps in a short time.

Contaminants or foreign matter in the oil will also damage the pumps . To prevent this, use a filter that captures particles as small as 30 microns or 30 millionths of a meter in diameter. You can help in the battle against dirt by being very careful when you remove or repair a component in the hydraulic system. Thoroughly clean off any component before you work on it. Plug the ends of any hose or line you remove with a rubber or plastic plug. Use plastic caps to seal off the ends of hydraulic fittings. Place any component you remove in a clean plastic bag so it can’t pick up dust or dirt. Clean your hands frequently when working on the hydraulic components.

Note: The pumps are not owner-repairable. If a pump fails, call our Service

Department for a replacement. Do not disassemble the pump.

4.Steering Lever Adjustments: Place the mower on level ground with the engine running, parking brake off and steering levers

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