NU CT424 Operator's Manual page 16

Machine has a
perceptible rolling
motion while running.
Clutch slipping or
sluggish response to
engine speed
change.
Thrust collar bushing?
Thrust bearing worn?
Main shaft?
Yoke?
Blade Pitch?
Worn V-belts?
Dirty centrifugal clutch?
Defective or worn out
centrifugal clutch?
Worn bearings in gearbox?
Worn or broken gears in
gearbox?
16
Check the thrust collar by
rocking it on the spider. If it can
tilt more than 3/32" (2.4mm) [as
measured at the thrust collar
O.D.], replace the bushing in the
thrust collar.
Check the thrust bearing to see
that it is spinning free. Note:
Thrust cap, replace if necessary.
The main output shaft of the
gearbox assembly should be
checked for straightness. The
main shaft must run straight and
cannot be more than 0.003"
(0.08mm) out of round at the
spider attachment point.
Check to make sure that both
fingers of the yoke press evenly
on the wear cap. Replace yoke
as necessary.
Check to ensure that each blade
is adjusted to have the same
pitch as all other blades. Adjust
per maintenance section in
manual.
Replace V-belt.
Disassemble and clean clutch.
Replace entire clutch.
Rotate input shaft by hand. If
shaft rotates with difficulty, check
the input and output shaft
bearings. Replace as necessary.
Verify that the gearbox shaft
rotates when the input shaft is
rotated.
Replace both the worm and
worm gear as a set.