How-To Troubleshoot A Gas Compressor
TROUBLESHOOTING
The following guide has been compiled to assist the consumer in identifying problems that may be encountered with gas compressors.
Please inspect for possible causes and contact an authorized service center when necessary.
| SYMPTOMS | POSSIBLE CAUSE | CORRECTIVE ACTION |
| Engine Wont Start | - Out of Gas - Oil Level Low - Switch is Off - Fuel Valve is Off - Engine Flooded - Bad Spark Plug - No Spark Plug - Engine Air Filter Wet, Clogged or Dirty - Defective low oil sensor switch |
- Refuel - Add Oil - Turned to "ON" - Turned to "ON" |
| Recoil Starter Pulls Very Hard | - Air pressure in the tanks | - Move hand unloader to 'Unload' position while starting |
| Compressor Wont Build Pressure | - Air Leak - Hand Unloader is in 'Unload' position - Worn piston cup and/or sleeve - Broken Flapper valve |
- Use a solution of soapy water to find air leaks - Move to 'Load' position - Remove head and valve plate to inspect, replace if needed - Remove head and valve plate to inspect, replace if needed |
| Engine Wont Return to High Speed | - Resistance in Throttle Control - Resistance in Throttle Linkage |
- Clean and lubricate the cable casing and control cylinder - Loosen friction nut on the throttle linkage of the engine |
| Safety Valve Blows Open and Engine Wont Return to Idle | - Control Valve Set Incorrectly | - With compressor running, adjust control valve by loosening the 9/16" hex while holding the 5/8" jam hex. Loosen slowly 1/8 turn at a time. |
| Compressor Slow to Recover | - Air Leak - Engine run speed too low - Control valve set incorrectly - Throttle cable out of adjustment - Worn piston cup and/or sleeve - Resistance in throttle control - Resistance in throttle linkage |
- Use a solution of soapy water to find leaks - Turn run speed adjustment screw (CCW) - Refer to Control Valve section for instructions to set correctly - Adjust throttle cable by removing the attachment screw and turning the attachment clip (clip is threaded) - Remove head and valve plate to inspect, replace if needed - Clean and lubricate the cable casing and control cylinder - Loosen friction nut on the throttle linkage of the engine |
| Compressor Recovers Fast | - Control valve set incorrectly - Air tanks full of water - Throttle cable out of adjustment |
- Refer to Control Valve section for instructions to set correctly - Drain water out of tanks - Adjust throttle cable by removing the attachment screw and turning the attachment clip (clip is threaded) |
| Excessive Vibration | - Engine speed out of adjustment - Resistance in throttle control - Resistance in throttle linkage |
- Adjust run speed to 3450 rpm +/- 150 rpm - Adjust idle speed to 2200 +/- rpm - Clean and lubricate the cable casing and control cylinder - Loosen friction nut on the throttle linkage of the engine - Adjust throttle cable by removing the attachment screw and turning the attachment clip (clip is threaded) - Tighten bolts that connect engine to baseplate of tank |
| Engine Quits | - Oil level low - Too much oil in engine - Engine idle speed too low - Resistance in throttle control - Resistance in throttle linkage |
- Add oil - Place on level surface, check oil level, drain if necessary -Turn idle speed adjustment screw (CW) to 2200 +/- rpm - Clean and lubricate the cable casing and control cylinder |
| Incorrect Cut-in/Cut-out Pressure | - Control valve set incorrectly | - Refer to Control Valve section for instructions to set correctly |
| Spark Plugs Wet/Fouled | - Engine idle speed too low - Engine run with choke on - Engine idles for long periods |
- Turn idle speed adjustment screw (CW) to 2200 +/- rpm - Set choke to run position when engine is running - Increase idle speed to 2500 +/- rpm to replace spark plug with a spark plug that is one of heat range 'hotter' - see authorized engine service center |
| Engine Speed Fluctuates | - Engine running out of fuel | - Refuel |
Engine Questions: Contact the engine manufacturer's authorized service center.
Compressor Questions: Contact Thomas Pumps and Compressors.
Control Valve Setting Instructions:
The control valve is preset at the factory to load at 115 psi and unload at 135 psi and should not require adjustment.
If adjustment is necessary, the unload pressure is adjusted by slightly turning the pressure adjusting nut (9/16" hex) while holding the locking nut (5/8" hex). Turn clockwise to increase and counterclockwise to decrease the unload pressure.
Changing the differential (the difference between the load and unload to pressure) is accomplished by holding the locknut (7/8" hex) closest to the body of the valve, then turning the differential nut (3/4" hex) very slightly. Turn clockwise to increase and counterclockwise to decrease the differential.