BOMBARDIER 1982 Shop Manual page 305

c
640 ENGINE TYPE
Two methods are detailed in this section; the first using
the timing marks stamped on the engine, the second us-
ing a Top Dead Center gauge.
Timing marks procedure
1. Disconnect spark plug wires and remove spark plugs.
2. Remove rewind starter assembly from engine then
remove the fan protector, starting pulley and "V"
belt .
O NaTE: The upper breaker point controls the tim-
ing of the magneto side piston and the lower
breaker point controls the P.T.O. side piston.
3. Rotate crankshaft until breaker points, visible through
magneto ring opening, are fully opened. Adjust points
setting to 0.30-0.40 mm (0.012-0 .016") using a feeler
gauge and screwdriver, as illustrated. Repeat pro-
cedure for other point. Adjust both sides equally.
O
NaTE: Breaker points gap can change upon tight-
ening. Always recheck after tightening .
4. Disconnect junction block at engine then connect
one lead of a timing light (flashlight type) to the blue
wire (mag . side) leading from engine. Connect other
wire to ground (metallic portion of the engine) .
5. Slacken the two (2) armature plate retaining screws
and turn timing instrument ON. Rotate crankshaft
until mag. side piston approaches top dead center
and timing marks align (for 640 engine type, hold
centrifugal advance mechanism in full advance posi-
tion).
SECTION 04 ELECTRICAL
SUB-SECTION 02 (IGNITION TIMING)
Retarted
?-WIIIIA---::"'~:r-
position
Full
advance
position
Rotate armature plate until timing light fluctuates. Re-
tighten retaining screws.
6. Ignition timing can change upon tightening therefore,
rotate the magneto counter-clockwise
1/4
of a turn
and slowly turn the magneto back in a clockwise di-
rection. As soon as the timing marks align the timing
light should fluctuate. Readjust if necessary.
Too early: Turn armature plate clockwise
Too late: Turn armature plate counter-clockwise
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