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7.2.5 SHEAVE ALIGNMENT
A set of V belts transmits rotational power to the rotor. They must be kept properly tensioned and the
sheaves aligned to obtain the expected performance and life.
For maximum accuracy, have your sheaves aligned with a laser alignment tool. Contact your dealer for
information on laser alignment.
Fig. 25 BELT DRIVE SYSTEM
Alignment may be carried out using a straight
edge, to check the alignment, follow this
procedure:
1. Clear the area of bystanders, especially small
children.
2. Turn machine off, stop engine, remove ignition
key and place in pocket and wait for all mov-
ing parts to stop.
3. Remove the belt guard and upper belt guard.
4. Have a straight edge at least 50" (127cm) in
length.
5. Place the straight edge along the face on the
back of the clutch, and place the opposite end
along the back face of the rotor sheave.
6. Check to see if there is a gap between the
straight edge and the clutch or the sheave,
measure the gap (A).
7. If there is more than 1/32" (.8mm) offset then
adjustment is required.
8. To adjust alignment:
a. Loosen the set screw on the bushing at-
tached to rotor sheave.
b. Remove the 3 hex bolts on the bushing,
and thread them into the tapped holes on
the bushing.
c. Tighten the hex bolts progressively with
1/4 turns until bushing is free from the
sheave taper.
d. Move the sheave to the required position
to align the belt.
e. If the offset is 1/32 (.8mm) or less then no
more adjustment is necessary.
Centrifugal
Clutch
Top view of belt drive system
A
Rotor
Sheave
Straight
Edge
Rotor
Sheave
Centrifugal
Clutch
Belt Drive
Straight
Edge
Note: movement of the
sheave may occur when
tightening the bushing, some
allowance for movement
may be required.
f. Align drilled holes with tapped holes on the
sheave, replace and hand tighten the 3 hex
bolts.
g. Tighten the set screw and recheck align-
ment.
h. Carefully tighten hex bolts progressively
(1/4 turns) and uniformly until firmly seated.
i. Recheck belt tension and assemble belt
guards.
Set Screw
Bushing
A