BOMBARDIER 1980 Shop Manual page 154

SECTION 03
SUB-SECTION
03,
(IGNITION TIMING)
e With gauge in adaptor. adjust roller so that it is
parallel with dial face. Tighten roller lock nut.
• Outer rmg set screw
Roller
lock nut
=-
e Loosen adaptor lock nut then holding gauge with
dial face toward magneto. screw adaptor in mag.
side spark plug hole.
e Slide gauge far enough into adaptor to obtain a
reading then finger tighten adaptor lock nut.
e Rotate magneto until mag. side piston is at top dead
center.
o Unlock outer ring of dial and turn it until "0" on
dial aligns with pointer.
s Lock outer ring in position.
6. Slacken the two (2) armature plate retaining screws
and turn timing
instrumen~
ON.
e Rotate magneto counter-clokwise until specified
piston position before top dead center is reached.
(IGNITION TIMING). PAGE 6
Engine
type
377
444
464
503
640
Direct
measurement
B.T.D.C.
207 mm ± 0.25
I
(.081" ±010)
2.35 mm ± 0.25
I
(.093" ±01O)
2.07 mm ± 0.251
(.081" ±010)
2.07 mm ± 0.25
(.081" ± .010)
N.A.
Indirect
measurement
B.T.D.C.
N.A.
NA
NA
NA
3.62 mm ± 0.25
(.143" ±01O)
Slowly rotate armature plate until timing light fluctuates
or until tone signal sound level varies. (For 640 engine
type, hold advance mechanism centrifugal lever in full
advance position.) Retighten retaining screws.
a
NOTE: Ignition timing can change upon tightening.
Always recheck after tightening.
7. Disconnect timing instrument wire from blue wire then
reconnect it to the blue I red wire leading from engine.
Remove T.D.C. gauge from mag. side and reinstall
It on P.T.O. side. as previously detailed.
8. Rotate crankshaft until P.T.O. piston approaches
T.D.C. As soon as same specified piston position before
top dead center as on mag. side is reached the timing
light should fluctuate or tone signal level vary. (for
640 engine type, hold advance mechanism in
full
advance position).
If necessary to adjust. proceed as follows.