Valve Clearance: Service and Repair

CAMSHAFT VALVE CLEARANCE

Inspection and Adjustment


INSPECTION

Perform inspection as follows after removal, replacement or installation of camshaft or valve-related parts, or if there are unusual engine conditions regarding valve clearance.
1.Remove rocker cover. Refer to "Removal and Installation" Removal And Installation.
2.Measure the valve clearance with the following procedure:
a.Set No. 1 cylinder at TDC of its compression stroke.





- Rotate crankshaft pulley (2) clockwise and align TDC mark (no paint) (A) to timing indicator (1) on front cover.










- At the same time, check that both intake and exhaust cam lobes of No. 1 cylinder face inside (black arrow) as shown in the figure.





- If the lobes do not face inside, rotate the crankshaft pulley 360
degrees to align as shown in the figure.





b.Use a feeler gauge (A) to measure the clearance between the valve lifter and camshaft.
Valve clearance: Refer to "Camshaft" [1][2]Camshaft, Engine.





- Refer to the figure. Using a feeler gauge, measure the valve clearances at locations marked "x" in the table below (also shown with black arrow (black arrow) in the figure).









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





- Rotate crankshaft pulley (2) one revolution (360 degrees) and align TDC mark (no paint) (A) to timing indicator (1) on front cover.










- Refer to the figure. Using a feeler gauge, measure the valve clearances at locations marked "x" in the table below (also shown with black arrow (black arrow) in the figure).









3.If out of the specifications, adjust as necessary. Refer to "ADJUSTMENT".

ADJUSTMENT

NOTE:
Proper valve clearance is obtained by selecting the correct valve lifter head thickness.
1.Remove camshaft. Refer to "Exploded View" Exploded View.
2.Remove valve lifters from the locations that are out of specification.





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.










- Thickness of new valve lifter (B) can be identified by stamp mark (A) on the under side of the lifter.
NOTE:
Available thickness of valve lifter: 26 sizes range 3.00 to 3.50
mm (0.1181 to 0.1378 in) in increments of 0.02 mm (0.0008 in)
when manufactured at factory. Refer to "Camshaft" [1][2]Camshaft, Engine.
- Stamp mark "302" indicates 3.02 mm (0.1189 in) in thickness.
5.Install the correct thickness valve lifter.
6.Install camshaft. Refer to "Exploded View" Exploded View.
7.Install timing chain and related parts. Refer to "Exploded View" Exploded View.
8.Manually rotate crankshaft pulley a few rotations.
9.Check that valve clearances are within specification. Refer to "INSPECTION".
10.Install remaining parts in the reverse order of removal.
11.Warm up the engine, and check for unusual noise and vibration.