03-24
SECTION 03 - ENGINE PREPARATION
TYPICAL
1. Solder
If rotary valve cover clearance is out of specifica-
tion, machine rotary valve cover seating surface
or replace the cover.
Machining Information
The amount of material over tolerance must be
removed from the rotary valve cover seating sur-
face.
Also cut the O-ring groove the same amount to
keep the 1.0
±
0.03 mm (.039
±
.001 in) depth be-
tween the bottom of the groove and the seating
surface.
Remove burrs on the edges of the seating surface
and O-ring groove.
SAME AMOUNT REMOVED FROM COVER SEATING SURFACE
AND O-RING GROOVE BASE
1. Cover seating surface
2. O-ring groove depth must be 1.0
±
0.03 mm (.039
±
.001 in)
Reverify the clearance.
At assembly the rotary valve timing must remain
as per original setting.
NOTE:
If rotary valve crankcase surface is worn,
it is possible to have it reworked at the factory.
Contact your dealer or distributor.
Crankshaft and Rotary Valve Shaft
Drive Gears Backlash
Remove PTO flywheel guard.
Remove spark plugs, rotary valve cover and valve.
Manually feel backlash at one position, then turn
crankshaft about 1/8 turn and recheck. Continue
this way to complete one revolution.
Backlash must be even at all positions. Other-
wise, disassemble engine to find which part is
faulty (drive gears or rotary valve shaft with exces-
sive deflection).
F01D3PA
1
1
2
F01D3OA
Summary of Contents for Bombardier
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