Lubrication & Maint./2000 Hour/24 Month Check and Adjust Valve Clearance (4045HF475 And 6068HF475 Engines) CAUTION: To prevent accidental starting of engine while performing valve adjustments, always disconnect NEGATIVE battery terminal. IMPORTANT: Valve clearance MUST BE checked and adjusted with engine COLD. 1. Remove rocker arm cover and crankcase ventilator tube. RG12168 –UN–03JUL02 IMPORTANT: Visually inspect contact surfaces of valve tips, bridges and rocker arm wear pads. Check all parts for excessive wear, breakage, or cracks. Replace parts that show visible damage.
Flywheel Housing Timing Holes A—Timing/Rotation Hole B—Timing Pin Hole Rocker arms that exhibit excessive valve clearance should be inspected more thoroughly to identify damaged parts. 2. Remove plastic plugs or cover plate from engine timing/rotation hole (A) and timing pin hole (B). NOTE: Some engines are equipped with flywheel housings which do not allow use of an engine flywheel rotation tool. These engines with straight nose crankshafts may be rotated from front nose of engine, using JDG966 Crankshaft Front/Rear Rotation Adapter. 3. Using JDE83 or JDG820 Flywheel Turning Tool, rotate engine flywheel in running direction (clockwise viewed from front) until No.
1 (front) cylinder is at TDC compression stroke. Insert JDG1571 or JDE81-4 Timing Pin in flywheel. If No. 1 cylinder rocker arms are loose, the engine is at No. 1 TDC compression. If No. 1 cylinder rocker arms are not loose, rotate engine one full revolution (360 ° ) to No. 1 TDC compression. Continued on next page OUO1089,0000208 –19–12MAR03–1/5 35-12 021604 PN=170