Troubleshooting
10
334644C
Troubleshooting
Problem
Cause
Solution
Air motor will not run and there is no
obvious exhaust
Check air supply
Supply air to motor inlet.
Pump is locked up.
Disconnect or remove pump to verify
motor operation.
Ice broke loose in manifold and
caught in air valve.
Turn off and exhaust air. Push top
and bottom valve shift buttons (118)
back and forth until flush with base of
valve cap (107). Restart motor.
Air motor doesn't run and large vol-
ume of air blows through exhaust
outlet on either stroke.
Main piston o-ring (10) has failed or
main valve. See below.
Replace piston o-ring (10) See page
10.
Air exhausts from rear outlet continu-
ously when motor is stalled against
• uid valve on one stroke or the other.
Shuttle valve cup (112) and plate
(105) failure.
Replace shuttle valve cup (112) and
plate (105).
Motor stalled at bottom of stroke with
no exhaust at bottom pilot. No
exhaust at top pilot.
Bottom pilot (15) is not exhausting.
Usually ice in the pilot or pilot
exhaust port.
Disconnect pilot line (55) for that
pilot. If motor changes over, bottom
pilot is plugged. Replace pilot
valve(55) and/or thaw ice that is
blocking air signal.
Metered air hole in main valve shuttle
piston (102) is plugged.
Disconnect pilot line (55). If motor still
doesn't change over, shuttle piston
metering hole is plugged. Clean or
replace shuttle valve piston assembly
(102).
Motor stalled at bottom of stroke with
exhaust at bottom pilot. Some
exhaust at top pilot.
Top pilot or • ttings are leaking air
when not activated by motor piston.
Tighten • ttings leak or replace top
pilot valve (15).
Motor stalled at top of stroke with no
exhaust at top pilot. No exhaust at
top pilot.
Top pilot (15) is not exhausting. Usu-
ally ice in the pilot or pilot exhaust
port.
Disconnect pilot line (55) for that
pilot. If motor changes over, top pilot
is plugged. Replace pilot valve(55)
and/or thaw ice that is blocking air
signal.
Metered air hole in main valve shuttle
piston (102) is plugged.
Disconnect pilot line (55). If motor still
doesn't change over, shuttle piston
metering hole is plugged. Clean or
replace shuttle valve piston assembly
(102)
Motor stalled at top of stroke with
exhaust at top pilot. Some exhaust at
bottom pilot.
Bottom pilot or • ttings are leaking air
when not activated by motor piston.
Tighten • ttings leak or replace bot-
tom pilot valve (15).
Air motor "bounces" at top change
over.
Leaking bottom pilot valve or fitting.
Thaw any ice in pilot valve, or replace
valve (15) if it is not ice.
Air motor "bounces" at bottom
change over.
Leaking top pilot valve or fitting.
Thaw any ice in pilot valve, or replace
valve (15) if it is not ice.
