23
MAINTENANCE SECTION
TROUBLESHOOTING GUIDE
Trouble
Probable Cause
Solution
Low power or low free speed
Insufficient air pressure
Check air line pressure at the Inlet of the tool. It must
be 90 psig (6.2 bar/620 kPa).
Clogged muffler elements
Disassemble the tool and agitate the bare Motor
Housing and Flange in a clean, suitable cleaning solu-
tion. If the elements cannot be cleaned, replace the
Motor Housing and/or the Flange.
Plugged Inlet Screen
Clean the Inlet Screen in a clean, suitable, cleaning
solution or replace the Screen.
Worn or broken Vanes
Install a complete set of new Vanes.
Loose Clamp Nut
Tighten the Nut to 20 to 25 ft–lb (27 to 34 Nm) torque.
Worn or broken Motor Housing
Replace the Motor Housing.
Internal air leakage in the Motor
Housing indicated by high air con-
sumption/low speed or air leaking
out the front and rear exhaust
simultaneously.
Replace the Motor Housing.
Grit buildup under the Throttle
Lever restricting full Throttle
Valve Plunger movement.
Remove the Throttle Lever and clean the groove in
the Motor Housing.
Bent stem on Throttle Valve
Replace the Throttle Valve
Front Seal Cup dragging against
the shield of the Front Rotor Bear-
ing
Reposition or replace the Front Seal Cup.
Scoring
Worn Front End Plate Spacer or
Front End Plate
Install a new Front End Plate Spacer and Front End
Plate.
Worn Front Rotor Bearing
Install a new Front Rotor Bearing.
Sanding Belt not tracking
Worn Idler parts
Install a new Idler Wheel Assembly
Misalignment
Adjust the Clevis Mounting Screws
Sanding on push side of Clevis
Sand on pull side of the Clevis.
