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To remove exhaust valve lifter, remove
cable from lifter arm. Remove securing
pin in top of rocker box and withdraw the
lifter complete with arm.
The rocker ball ends and valve rocker
pads are pressed into the rocker arms and
may be knocked out for replacement.
20. TAPPET OR PUSH ROD ADJUST
MENT ON MACHINES WHERE
ENGINE NO. IS FOLLOWED BY
THE LETTER Q.
Engines having a number followed by the
above suffix are fitted with a modified cam
form which requires rather more careful
positioning of the cam than previously.
For both O.H.V. and S.V. engines pro
ceed as follows:—
To adjust inlet valve clearance rotate
engine till exhaust valve is just lifting.
Adjust inlet tappet or push rod (para. 21).
To adjust exhaust valve clearance rotate
engine till inlet valve has just closed. Adjust
exhaust tappet or push rod.
On S.V. engines there should be .010"
clearance between tappet head and valve on
inlet and exhaust.
On O.H.V. engines both push rods should
be free to rotate without any up and down
movement.
.Set clearances with engine cold.
When timing engine with these cams there
should be a .017" feeler inserted between
cam and crankcase rocker pad.
Adjust afterwards to correct clearance.
21. TO ADJUST TAPPETS OR PUSH
RODS.
Release the middle hexagon—locking the
nut—by placing one spanner on the bottom
hexagon—the tappet stem or push rod—and
the second on the locking nut. (Fig. 6-7.)
Turn the top hexagon—the tappet head or
push rod adjuster—in the desired direction,
and when the correct clearance is obtained,
tighten locking nut.
Check clearance after tightening locking
nut.
Fig. 7.
O.H.V. PUSH ROD ADJUSTMENT.
SEAUNfi WAfl>4ra
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o c k o u t
Fig. 6.
S.V. TAPPET ADJUSTMENT
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