Trouble
Low power or low free speed
Rough operation
Scoring
Air leaks
SAVE THESE INSTRUCTIONS. DO NOT DESTROY.
MAINTENANCE SECTION
TROUBLESHOOTING GUIDE
Probable Cause
Low air pressure at the Inlet
Plugged Inlet Bushing Screen
Worn or broken Vanes
Worn or broken Cylinder
Improper lubrication or dirt
build–up in the motor
Worn or broken Rear Rotor
Bearing or Front Rotor Bearing
Worn Rotor Key
Bent Arbor
Improper assembly
Rotor Bearing Seal misalignment Losen the Cylinder Case Screws. Rotate the Spindle
Worn Valve Seat or Valve Seat
Washer
Worn Throttle Valve Seals
Solution
Check the air pressure at the Inlet. The pressure
must not exceed 90 psig (6.2 bar/620 kPa).
Clean the Screen in a clean, suitable, cleaning
solution. If it cannot be cleaned, replace it.
Never operate a Sander without an Inlet Screen.
Ingestion of dirt into the Sander can, in some
cases, cause an unsafe condition.
Replace a complete set of Vanes.
Replace the Cylinder if it is worn or broken or if the
bore is scored or wavy.
Lubricate the Sander as instructed in
LUBRICATION SPECIFICATION. If
lubrication does not result in satisfactory operation,
disassemble the motor and inspect and clean all
parts.
Examine each Bearing. Replace the Rear Rotor
Bearing Seal Assembly if worn or damaged or
replace the Front Rotor Bearing.
Replace the Key. Check the Arbor and Rotor for key
slot wear and replace if necessary.
Mount the Arbor on centers. Check the bearing
diameter runout with an indicator. Replace the
Arbor if runout exceeds 0.002" Total Indicator
Reading.
Make certain that all motor parts are properly
aligned prior to clamping the motor assembly.
by hand to align the Seal. Retighten the Screws to
14 ft–lb (19 Nm) torque. The Spindle must rotate
freely.
Replace worn parts.
Replace both Seals.