Ingersoll-Rand 61H120, Operation And Maintenance Manual

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23
MAINTENANCE SECTION
TROUBLESHOOTING GUIDE
Trouble Probable Cause Solution
Low power or low free speed Insufficient air pressure at the
inlet Check the air pressure at the inlet. It must be
90 psig (6.2 bar/620 kPa).
Plugged Screen Clean the Inlet Bushing Screen in a clean, suitable,
cleaning solution. If it cannot be cleaned,
replace it.
Never operate a Grinder without an Inlet
Bushing Screen. Ingestion of dirt into the Grinder
can, in some cases, cause an unsafe condition.
Worn or broken Vanes Replace a complete set of new Vanes.
Worn or broken Cylinder Replace the Cylinder if it appears cracked or if the
bore is wavy or scored.
Improper lubrication or dirt build–
up in the motor Lubricate the Grinder as instructed in
LUBRICATION. If lubrication does not result in
satisfactory operation, disassemble the motor, clean
and inspect all parts.
Rough operation Worn or broken Rear Rotor Bear-
ing Assembly or Front Rotor
Bearing Examine each bearing. Replace the Rear Rotor Seal
Assembly if worn or damaged or replace the Front
Rotor Bearing.
Bent Arbor Mount the Arbor on centers. Check bearing
diameter runout with an indicator. Replace the Ar-
bor if runout exceeds 0.002” (0.051 mm) Total Indi-
cator Reading.
Scoring Improper assembly Make certain that all motor parts are properly
aligned prior to installing the Handle Assembly into
the Arbor Housing.
Air leaks Worn Valve Seat or Valve Seat
Washer Replace worn parts.
Worn Throttle Valve Seals Replace both Seals.
Oil Chamber Plug worn or not
tight Tighten the Plug. If the problem persists, replace the
Plug.
High free speed Worn Rear End Plate Assembly
and/or Controller Seal Replace the Rear End Plate Assembly if the large in-
side diameter of the Rear End Plate is worn to 1.156”
(38.506 mm) or larger and/or the outside diameter of
the Controller Seal is worn to 1.511” (38.379 mm) or
smaller.
Grinder will not run Coupling Nut too tight Loosen Coupling Nut and retighten to 47.5 to
52.5 ft–lb (64.5 to 71.5 Nm) torque.
Do not exceed 52.5 ft–lb (71.5 Nm) torque.
SAVE THESE INSTRUCTIONS. DO NOT DESTROY.