Rocker Arm Shaft; Inspection Of Rocker Arm And Rocker Arm Shaft - TOHATSU MFS 60A Service Manual

Power Unit
9. Apply thin coat of abrasive compound on the overall valve
seat contact area, and turn valve lapper (commercially
available item) while tapping valve.
Per form the work by taking care not to allow
abrasive compound to adhere to valve stem and
valve guide.
• Use finer abrasive compound to finish.
• When changing abrasive compound to finer one,
remove present one completely.
• After completion of lapping, wipe off the
compound and then clean.
10. After ending the work, remove the compound completely
from cylinder head and valve.
Check valve seat contact width c.
11.
Valve Seat Contact Width c : Standard Value
1.4 mm (0.06 in)
14) Inspection of Rocker Arm and Rocker Arm
Shaft
1. Check rocker arm, rocker arm shaft and rocker arm contact
area a for wear. Replace if necessary.
Measure rocker arm inner diameter b and rocker arm shaft
2.
outer diameter c. Obtain oil clearance d (d = b – c).
Replace if the clearance is out of specified range.
Rocker Arm Inner Diameter b : Standard Value
18.01 mm (0.7091 in)
Rocker Arm Shaft Outer Diameter c : Standard Value
17.99 mm (0.7083 in)
Oil Clearance Between Rocker Arm Hole
and Shaft d : b – c
0.006 to 0.035 mm (0.00024 to 0.00138 in)
Functional Limit :
Replace if b is over 18.05 mm (0.7106 in).
Replace if c is less than 17.94 mm (0.7063 in).
Replace if d is over 0.090 mm (0.00354 in).
5-32
CAUTION
b Width before correction
a
c
b
d = b – c
b
c
45˚
4st 60 2019