Valve Clearance: Adjustments
Valve ClearanceADJUSTING
NOTE: Adjust valve clearance while engine is cold.
1. Turn crankshaft clockwise (viewed from front) to position cam lobe upward on camshaft for valve that must be adjusted.
2. Turn valve lifter and adjusting shim to removal direction.
^ Using a slotted screwdriver with an extra-thin tip, turn the valve lifter cutout in the direction shown by the arrow.
3. Place Tool (1) around camshaft as shown.
Tool number: 45074-1
NOTE: Before placing Tool (1), rotate notch toward center of cylinder head. This will simplify shim removal later.
CAUTION:
^ Be careful not to damage camshaft and cylinder head.
^ Be careful not to damage surroundings of valve lifter.
4. Rotate Tool (1) so that valve lifter is pushed down, compressing the spring.
5. Place Tool (2) between camshaft and valve lifter to retain valve lifter. Tool number: 45074-2
CAUTION:
^ If camshaft pliers are suddenly turned back, the lifter stopper may contact and damage the camshaft journals. Turn back the camshaft pliers carefully to remove.
^ Tool (2) must be placed as close to camshaft bracket as possible.
^ Be careful not to damage cam surface with Tool (2).
6. Remove Tool (1).
7. Remove adjusting shim using Tool and a magnetic finger.
8. Determine replacement adjusting shim size using the following formula.
^ Use a micrometer to determine thickness (t1) of removed shim at camshaft contact face (around center).
^ Use t1 + (C1-C2) to calculate thickness of new adjusting shim so valve clearance comes within specified values.
t1 = Thickness of removed shim
C1 = Measured valve clearance
C2 = Standard valve clearance
Hot engine:
Intake: 0.32 - 0.40 mm (0.013 - 0.016 inch)
Exhaust: 0.37 - 0.45 mm (0.015 - 0.018 inch)
Reference values with cold engine:
Intake: 0.25 - 0.33 mm (0.010 - 0.013 inch)
Exhaust: 0.32 - 0.40 mm (0.013 - 0.016 inch)
^ Thickness of new adjusting shim is indicated with stamped mark on its back.
^ Shims are available in 50 sizes from 2.00 mm (0.0787 inch) to 2.98 mm (0.1173 inch), in steps of 0.02 mm (0.0008 inch).
^ Select the closest size shim to the calculated thickness. Refer to AVAILABLE SHIMS.
Part 1:
Part 2:
Part 3:
AVAILABLE SHIMS
9. Install new shim using Tool (2).
Tool number: 45074-2
^ Install with the surface on which the thickness is stamped facing down.
10. Place Tool (1) as explained in steps 4 and 5.
11. Remove Tool (2).
12. Remove Tool (1).
13. Turn the crankshaft a couple of times by hand.
14. Recheck the valve clearance.