4 - 20
ENG
CAMSHAFT, ROCKER ARMS AND VALVES
2.Check:
●
Rocker arms
●
Rocker arm shafts
Damage/wear → Replace.
*****************************************************
Checking steps:
●
Check the two contact areas on the rocker
arms for signs of abnormal wear.
1) Rocker arm shaft hole
2) Camshaft lobe contact surface
Excessive wear → Replace.
●
Check the surface of the rocker arm shafts.
Blue discoloration/pitting/scratches →
Replace/check lubrication.
●
Measure the inside diameter a of the rocker
arm holes.
Out of specification → Replace.
●
Measure the outside diameter b of the
rocker arm shafts.
Out of specification → Replace.
●
Calculate the clearance by subtracting the
rocker arm shaft outside diameter from the
rocker arm inside diameter.
Clearance greater than 0.08 mm (0.003 in)
→ Replace the defective part(s).
*****************************************************
Rocker arm inside diameter:
12.000 ~ 12.018 mm
(0.4724 ~ 0.4731 in)
Rocker arm outside diameter:
11.981 ~ 11.991 mm
(0.4717 ~ 0.4721 in)
Rocker arm to shaft standard
clearance:
0.009 ~ 0.037 mm
(0.0004 ~ 0.0015 in)