20
Low discharge
pressure.
1. Air demand exceeds
pump capacity.
1. Reduce air demand or use a compressor with
more capacity.
2. Restricted air intake.
2. Clean or replace the air filter element.
3. Air leaks (fittings,
tubing on compressor,
or plumbing outside of
system).
3. Listen for escaping air. Apply soap solution to
all fittings and connections. Bubbles will appear
at points of leakage. Tighten or replace leaking
fittings or connections. Use pipe thread sealant.
4. Blown gaskets.
4. Replace any gaskets proven faulty on
inspection.
5. Leaking or damaged
valves.
5. Remove head and inspect for valve breakage,
misaligned valves, damaged valve seats, etc.
Replace defective parts and reassemble.
CAUTION
Unit Care and Maintenance.
Install a new
head gasket each time the head is removed.
Excessive noise
(knocking).
1. Loose motor pulley or
flywheel.
1. Tighten pulley / flywheel clamp bolts and set-
screws.
2. Loose fasteners on pump
or motor.
2. Tighten fasteners.
3. Lack of oil in crankcase.
3. Check for proper oil level; if low, check for
possible damage to bearings. Dirty oil can cause
excessive wear.
4. Worn connecting rod.
4. Replace connecting rod. Maintain oil level and
change oil more frequently.
5. Worn piston pin bores.
5. Remove piston assemblies from the compressor
and inspect for excess wear. Replace
excessively worn piston pin or pistons, as
required. Maintain oil level and change oil more
frequently.
6. Piston hitting the valve
plate.
6. Remove the compressor head and valve plate
and inspect for carbon deposits or other foreign
matter on top of piston. Replace head and valve
plate using new gasket. See Lubrication section
for recommended oil.
7. Noisy check valve in
compressor system.
7. Replace check valve.
Risk of Explosion.
Do not
disassemble check valve with air
pressure in tank.
DANGER
TROUBLESHOOTING
PROBLEM
POSSIBLE CAUSE
CORRECTIVE ACTION
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