Inspection
INSPECTIONAdjusting Screw and Rocker Arm
If tip of adjusting screw is badly worn, replace it. Rocker arm must be replaced if its cam-riding face is badly worn.
Rocker Arm Shaft Runout
Using "V" blocks and dial gauge, check runout. If runout exceeds its limit, replace rocker arm shaft.
Runout limit: 0.20 mm (0.008 inch)
Rocker Arm-to-Rocker Arm Shaft Clearance
Using a micrometer and a bore gauge, measure rocker shaft diameter and rocker arm I.D. Difference between two readings is arm-to-shaft clearance on which a limit is specified. If limit is exceeded, replace shaft or arm, or both.
Rocker Arm I.D.:
Standard: 15.985- 16.005 mm (0.629 - 0.630 inch).
Rocker Arm Shaft Diameter:
Standard: 15.969- 15.984 mm (0.6287 - 0.6293 inch).
Arm-to-Shaft Clearance:
Standard: 0.001 - 0.036 mm (0.0001 - 0.0014 inch).
Limit: 0.09 mm (0.0035 inch).
Cam Wear
Using a micrometer, measured height of cam. If measured height is below limit, replace camshaft.
Cam Height:
Intake Cam:
Standard: 36.171-36.331 mm (1.4241 - 1.4303 inch)
Limit: 36.071 mm (1.4202 inch)
Exhaust Cam:
Standard: 36.356 - 36.516 mm (1.4314- 1.4376 inch)
Limit: 36.256 mm (1.4275 inch)
Camshaft Runout
Hold camshaft between two "V" blocks, and measure runout by using a dial gauge. If runout exceeds the limit, replace camshaft.
Runout limit: 0.10 mm (0.0039 inch).
Camshaft Journal Wear
Check camshaft journals and camshaft housings for pitting, scratches, wear or damage. If any malcondition is found, replace camshaft or cylinder head with housing. Never replace cylinder head without replacing housing.
Check clearance by using gaging plastic. The procedure Was follows:
1. Clean housing and camshaft journals.
2. Install camshaft to cylinder head.
3. Place a piece of gaging plastic the full width of journal of camshaft (parallel to camshaft).
4. Install camshaft housing.
5. Tighten camshaft housing bolts in such order as indicated in figure a little at a time till they are tightened to specified torque.
Tightening Torque (a): 11 Nm (1.1 kg-m, 8.0 ft. lbs.).
NOTE: Do not rotate camshaft while gauging plastic is installed.
6. Remove housing and using scale on gaging plastic envelope, measure gauging plastic width at its widest point.
Journal Clearance:
Standard: 0.040 - 0.082 mm (0.0016 - 0.0032 inch).
Limit: 0.12 mm (0.0047 inch).
If measured camshaft journal clearance exceeds limit, measure journal (housing) bore and outside diameter of camshaft journal. Replace camshaft or cylinder head assembly whichever the difference from specification is greater.
Camshaft Journal Bore Diameter: 28.000-28.021 mm (1.1024- 1.1031 inch).
Camshaft journal O.D.: 27.939 - 27.960 mm (1.1000 - 1.1008 inch).