Valve Clearance: Testing and Inspection
Valve ClearanceINSPECTION
NOTE: The following procedure is applicable when: components related to camshafts or valves are removed, installed, or replaced. Driveability concerns (poor starting, poor idling, noise) are caused by valve clearance aging.
1. Warm engine and stop.
2. Remove RH splash cover.
3. Remove the rocker cover. Refer to ROCKER COVER.
4. Remove all of the spark plugs.
5. Set No. 1 cylinder at TDC on its compression stroke.
^ Align pointer with TDC mark on crankshaft pulley.
^ Check that both intake and exhaust cam noses on No. 1 cylinder face outward.
^ If not, turn crankshaft one revolution (360°) and align as described above.
NOTE: Or, valves to be checked when No. 4 cylinder is at TDC of its compression stroke can be checked first following step 8.
6. Referring to figure, measure valve clearances of valves with x in table below using. a thickness gauge.
^ Using a feeler gauge, measure clearance between valve lifter and camshaft.
^ Record any valve clearance measurements which are out of specification. They will be used later to determine the required replacement adjusting shim.
7. Turn crankshaft one revolution (360°) to position No. 4 cylinder at TDC of its compression stroke.
8. Check only those valves shown in the figure and marked with an x in the table.
9. If outside the standard, adjust applicable valves. Refer to ADJUSTING.