TUBE 1212023 - Caterpillar

You must read and understand the warnings and instructions contained in the Safety section of this manual before performing any operation or maintenance procedures.Engine Valve Lash
Adjust
To prevent possible injury, do not use the starter motor to turn the flywheel.Hot engine components can cause burns. Allow additional time for the engine to cool before measuring valve clearance.
Measure the valve lash with the engine stopped. To obtain an accurate measurement, allow at least 20 minutes for the valves to cool to engine cylinder head and block temperature.
Adjust the valve clearance to within 0.08 mm (.003 in) of the valve clearance setting given. Refer to the Service Manual or your Caterpillar dealer for the complete valve adjustment procedure. After setting valve clearances and before installing the valve cover, check the valve rotators. See next topic.Engine Valve Rotators
Observe Rotation of Valves With Engine Idling After Setting the Valve Clearances
When inspecting the valve rotators, protective glasses or face shield and protective clothing must be worn, to prevent being burned by hot oil spray.
After setting all valve clearances and before installing the valve cover:1. Start the engine.2. Move the governor control to low idle position. 3. Watch the top surface on each valve rotator. Each valve rotator should turn slightly each time the valve closes.If a valve fails to rotate, contact your Caterpillar dealer.Steering Control Mechanism
Check Oil Level
The steering control mechanism is located behind the engine. 1. Remove fill plug.2. Oil should be to the bottom of the fill plug opening. Add oil if necessary.3. Install the fill plug.Parking Brake Pads
Inspect - replace
Pads should be replaced when the lining thickness on the front pad (1) is less than 10 mm (.38 inch).1. Remove cap (2) over hole in center of the input lever assembly.2. Insert a .25 inch Allen wrench through hole into end of rod and turn counterclockwise until rod is backed out fully.3. Remove cotter pins (3) and slide retaining pins (4) out to remove old pads.4. Insert new pads with thinner pad to rear of machine.5. Replace pins and cotters.6. Use Allen wrench to turn rod clockwise until pad to rotor gap is 0.38 mm (.015 inch) on each side of the rotor.7. Replace the cap on hole in lever assembly.8. Final pad adjustment is done from the cab by alternately applying and releasing the parking brake handle until the lever travel decreases and then remains constant.Brake Accumulator
Measure Pressure
The accumulator is precharged to 2100 kPa (300 psi). Discharge all gas and hydraulic pressure by pumping the brake pedal inside the cab until it is difficult to depress.Be absolutely sure that all pressure is discharged from the accumulator before disconnecting the supply line or disassembling the accumulator. Your Caterpillar dealer is equipped to measure the accumulator precharge pressure. Use only dry nitrogen gas for recharge.