Valve Clearance: Testing and Inspection

Valve Clearance

INSPECTION
In cases of removing/installing or replacing camshaft and valve-related parts, or of unusual engine conditions due to changes in valve clearance (found malfunctions during starting, idling or causing noise), perform inspection as follows:
1. Remove rocker covers (right and left bank).
2. Measure the valve clearance as follows:
a. Set No. 1 cylinder at TDC of its compression stroke.





^ Rotate crankshaft pulley in clockwise to align TDC identification notch (without paint mark) with timing indicator on front cover.





^ Make sure that both intake and exhaust cam noses of No. 1 cylinder (engine front side of left bank) are located as shown in the figure.
^ If not, turn crankshaft one revolution (360 degrees) and align as shown in the figure.





b. Use feeler gauge, measure the clearance between valve lifter and camshaft.

Valve clearance:

^ By referring to the figure, measure the valve clearances at locations marked "x" as shown in the table below (locations indicated with black arrow in figure).

NOTE:
Firing order 1-8-7-3-6-5-4-2

^ No. 1 cylinder at compression TDC





c. Rotate crankshaft pulley clockwise (when view from engine front) by 270 degrees from the position of No. 1 cylinder compression TDC to align No. 3 cylinder at TDC of its compression stroke.

NOTE:
Crankshaft pulley mounting bolt flange has a angle mark every 90 degrees. They can be used as a guide to rotation angle.








^ By referring to the figure, measure the valve clearances at locations marked "x" as shown in the table below (locations indicated with white arrow in figure).
^ No. 3 cylinder at compression TDC





d. Rotate crankshaft pulley clockwise (when view from engine front) by 90 degrees from the position of No. 3 cylinder compression TDC to align No. 6 cylinder at TDC of its compression stroke.








^ By referring to the figure, measure the valve clearances at locations marked "x" as shown in the table below.
^ No. 6 cylinder at compression TDC
3. For the measured value are out of the standard, perform adjustment. Refer to "ADJUSTMENT".