Valve Clearance: Adjustments
CHECKINGCheck valve clearance while engine is cold and not running.
1. Remove intake manifold collector.
2. Remove rocker ornament covers.
3. Remove RH and LH rocker covers.
4. Remove all spark plugs.
5. Set No. 1 cylinder at TDC on its compression stroke.
- Align pointer with TDC mark on crankshaft pulley.
- Check that valve lifters on No. 1 cylinder are loose and valve lifters on No. 4 are tight.
If not, turn crankshaft one revolution (360°) and align as above.
6. Check only those valves shown in the image.
- 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.
Valve clearance for checking (Cold):
Intake: 0.26 - 0.34 mm (0.010 - 0.013 inch)
Exhaust: 0.29 - 0.37 mm (0.011 - 0.015 inch)
7. Turn crankshaft 240° and align as above.
8. Set No. 3 cylinder at TDC on its compression stroke.
9. Check only those valves shown in the image.
10. Turn crankshaft 240° and align as above.
11. Set No. 5 cylinder at TDC on its compression stroke.
12. Check only those valves shown in the image.
13. If all valve clearances are within specification, install the following parts. Intake manifold collector RH and LH rocker covers All spark plugs Rocker cover ornament.
ADJUSTING
Adjust valve clearance while engine is cold.
1. Turn crankshaft, to position cam lobe on camshaft of valve that must be adjusted upward.
2. Place Tool (A) around camshaft as shown in image.
Before placing Tool (A), rotate notch toward center of cylinder head (See image.), to simplify shim removal later.
CAUTION: Be careful not to damage cam surface with Tool (A).
3. Rotate Tool (A) (See image.) so that valve lifter is pushed down.
4. Place Tool (B) between camshaft and the edge of the valve lifter to retain valve lifter.
CAUTION:
- Tool (B) must be placed as close to camshaft bracket as possible.
- Be careful not to damage cam surface with Tool (B).
5. Remove Tool (A).
6. Blow air into the hole to separate adjusting shim from valve lifter.
7. Remove adjusting shim using a small screwdriver and a magnetic finger.
8. Determine replacement adjusting shim size following formula.
- Using a micrometer determine thickness of removed shim.
- Calculate thickness of new adjusting shim so valve clearance comes within specified values.
R = Thickness of removed shim
N = Thickness of new shim
M = Measured valve clearance
Intake: N = R + [M - 0.30 mm (0.0118 inch)]
Exhaust: N = R + [M - 0.33 mm (0.0130 inch)]
Shims are available in 64 sizes from 2.32 mm (0.0913 inch) to 2.95 mm (0.1161 inch), in steps of 0.01 mm (0.0004 inch).
- Select new shim with thickness as close as possible to calculated value.
9. Install new shim using a suitable tool.
- Install with the surface on which the thickness is stamped facing down.
Valve Clearance:
10. Place Tool (A) as mentioned in steps 2 and 3.
11. Remove Tool (B).
12. Remove Tool (A).
13. Recheck valve clearance.