BOMBARDIER SEA-DOO SPX 5838 1998 Shop Manual page 116

Section 04 ENGINE
Subsection 06 (BOTTOM END)
To accurately check if crankshaft is twisted on
center main journal, proceed as follows:
– Remove magneto housing cover.
– Remove flywheel nut (and magneto rotor for
the 787 and 947 engines). Refer to MAGNETO
SYSTEM 04-04 for procedures.
– Install Bombardier degree wheel (P/N 295 000
007) on crankshaft end. Hand-tighten nut only.
– Remove both spark plugs.
– Install a TDC gauge in spark plug hole on MAG
side.
– Bring MAG piston at Top Dead Center.
– As a needle pointer, secure a wire with a cover
screw and a washer.
– Rotate degree wheel (NOT crankshaft) so that
needle pointer reads 360°.
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3
F01D4IA
TYPICAL
1. TDC gauge
2. Degree wheel
3. Hand tighten nut
4. Needle pointer
– Remove TDC gauge and install on PTO side.
– Bring PTO piston at Top Dead Center.
Interval between cylinders must be exactly 180°
therefore, needle pointer must indicate 180° on
degree wheel (360° - 180° = 180°).
Any other reading indicates a misaligned crank-
shaft.
04-06-12
Crankshaft Alignment at Connecting
Rod Journal
Counterweights can also be twisted on connect-
ing rod journal on any or both cylinder(s).
F01D1NB
1. Connecting rod journal alignment here
Such misalignment may cause a crankshaft hard
to be manually turned. Verification can be done by
measuring deflection each end of crankshaft.
2
If deflection is found greater than specified toler-
ance, this indicates worn bearing(s), bent and/or
disaligned crankshaft. Proceed with the disas-
sembly of the engine.
Disassembled Engine
4 The following verifications can be performed with
the engine disassembled.
2, Crankcase
Inspect plane surfaces for warpage. Small defor-
mation can be corrected by grinding surface with
a fine sandpaper. Install sandpaper on a surface
plate and rub part against oiled sand paper.
4, Bearing
Inspect crankshaft bearings. Check for corrosion,
scoring, pitting, chipping or other evidence of
wear. Make sure plastic cage is not melted. Ro-
tate and make sure they turn smoothly.
3, Crankshaft
NOTE: If crankshaft and/or components are found
defective, it must be repaired by a specialized
shop or replaced.
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