KIT-SEAL 2453749 - Caterpillar

Inspecting Valve Clearance
Inspect and adjust the valve clearance when the engine is cold.
Table 1
Item        
Valve clearance (when engine is cold)     Inlet    
0.250 mm (0.0098 inch)    
Exhaust
Illustration 1 g02242673
Inspect the valve clearance for all cylinders in the firing order by turning the crankshaft to the specified degrees in the normal direction (clockwise when viewed from engine front side) to bring each piston to the top dead center on the compression stroke.Note: To turn the crankshaft, fit a turning handle (1) on the crankshaft pulley nut.
Illustration 2 g02242674
When the No.1 piston is at the top dead center on the compression stroke. The "0" graduation mark on the periphery of the crankshaft pulley is aligned with the pointer on the timing gear case. The inlet valve or the exhaust valve is not lifted off the seat by the push rod.
Insert a thickness gauge between the rocker arm and valve cap to inspect the clearance.Adjusting Valve Clearance
Illustration 3 g02242675
(A) valve clearance 0.250 mm (0.0098 inch) (2) Adjustment screw (3) Lock nut
Insert the feeler gauge of the specified thickness between the rocker arm and bridge cap. Then adjust the clearance by turning the screw in either direction so that the gauge is gripped softly between the rocker arm and bridge cap.
After adjusting the clearance, tighten the lock nut firmly, and inspect the clearance again.
Turn the engine and check the valve clearance on the remaining cylinders. The inspection sequence and turning angle are as follows:
Table 2
Sequence (Cylinder No.)    Turning Angle    
1-3-4-2     180°    
When adjusting the valve clearance after disassembly, rotate the crankshaft 2 or 3 turns after adjustment and recheck the valve clearance to make sure that the clearance conforms to the specification.