Valve Clearance: Testing and Inspection

CAMSHAFT

Valve Clearance


INSPECTION

Perform inspection as follows after removal, installation or replacement of camshaft or valve-related parts, or if there is unusual engine conditions regarding valve clearance.
1.Remove rocker cover.
2.Measure the valve clearance with the following procedure:
a.Set No. 1 cylinder at TDC of its compression stroke.
- Rotate crankshaft pulley (1) clockwise and align TDC mark (no paint) (B) to timing indicator (A) on front cover.















- At the same time, make sure that both intake and exhaust cam noses of No. 1 cylinder face inside () as shown.





- If they do not face inside, rotate crankshaft pulley once more (360 degrees) and align as shown.





b.Use a feeler gauge, measure the clearance between valve lifter and camshaft.
Valve clearance:
Unit: mm (in)










- By referring to the figure, measure the valve clearances at locations marked x
as shown in the table below [locations indicated with black arrow (black arrow)] with a feeler gauge.
- No. 1 cylinder compression TDC










c.Set No.4 cylinder at TDC of its compression stroke.





- Rotate crankshaft pulley (1) one revolution (360 degrees) and align TDC mark (no paint) (B) to timing indicator (A) on front cover.










- By referring to the figure, measure the valve clearance at locations marked x as shown in the table below [locations indicated with black arrow (black arrow)] with a feeler gauge.
- No. 4 cylinder compression TDC










3.If out of standard, perform adjustment.

ADJUSTMENT

- Perform adjustment depending on selected head thickness of valve lifter.
1.Remove camshaft. Removal And Installation.
2.Remove valve lifters at the locations that are out of the standard.





3.Measure the center thickness of the removed valve lifters with a micrometer (A).
4.Use the equation below to calculate valve lifter thickness for replacement.
Valve lifter thickness calculation:t = t1 + (C1- C2)
t= Valve lifter thickness to be replaced t
1= Removed valve lifter thickness
C1= Measured valve clearance
C2= Standard valve clearance:
Intake: 0.30 mm (0.012 in)
Exhaust: 0.33 mm (0.013 in)





- Thickness of new valve lifter (B) can be identified by stamp mark (A) on the reverse side (inside the cylinder).
Stamp mark "302" indicates 3.02 mm (0.1189 in) in thickness.
NOTE:
Available thickness of valve lifter: 26 sizes range 3.00 to 3.50 mm (0.1181 to 0.1378 in) in steps of 0.02
mm (0.0008 in) (when manufactured at factory). [1][2]Specifications.
5.Install the selected valve lifter.
6.Install camshaft. Removal And Installation.
7.Install timing chain and related parts.
8.Manually rotate crankshaft pulley a few rotations.
9.Make sure that the valve clearances is within the standard.
10.Installation of the remaining components is in the reverse order of removal.