Valve Clearance: Testing and Inspection

INSPECTION

NOTE:
Perform the following inspection after removal, installation or replacement of camshaft or valve-related parts, or if there are unusual engine conditions due to changes in valve clearance over time (starting, idling, and/or noise).

1. Warm up the engine. Then stop the engine.
2. Remove the engine room cover.
3. Remove the air cleaner and air duct assembly.
4. Remove the RH bank and LH bank rocker covers using power tool.

5. Turn the crankshaft pulley in the normal direction (clockwise when viewed from engine front) to align TDC identification notch (without paint mark) with timing indicator.

6. At this time, make sure both the intake and exhaust cam noses of No. 1 cylinder (top front on LH bank) face outside.
^ If they do not face outside, turn crankshaft pulley once more.

7. Measure valve clearances at the locations marked "x" as shown in the table below (locations indicated with black arrow).
^ <---: Engine front
^ <--- (black): Measurable at No.1 cylinder compression top dead center
^ <--- (white): Measurable at No.3 cylinder compression top dead center
^ A: RH
^ B: LH
^ C: Exhaust
^ D: Intake

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

^ No. 1 cylinder compression TDC

9. Measure valve clearances at the locations marked "x" as shown in the table below (locations indicated with white arrow).
^ <---: Engine front
^ <---: (black): Measurable at No.1 cylinder compression top dead center
^ <---: (white): Measurable at No. 3 cylinder compression top dead center
^ A: RH
^ B: LH
^ C: Exhaust
^ D: Intake

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

^ No. 3 cylinder compression TDC

^ Measure valve clearance using suitable tool.

CAUTION:
If the inspection was carried out with a cold engine, make sure the values with a fully warmed up engine are still within specifications.

10. Turn the crankshaft pulley clockwise 90° from the position of No. 3 cylinder compression TDC (clockwise by 360° from the position of No. 1 cylinder compression TDC) to measure the intake and exhaust valve clearances of No. 6 cylinder and the exhaust valve clearance of No. 2 cylinder.
11. If out of specifications, adjust as necessary.