How-To Troubleshoot An Air Compressor
Troubleshooting your compressor
Problem:
My unit trips the breaker when it tries to restart after filling the tank the first time.
Solution:
- Let your unit pump up.
- Turn it off.
- Find the supply line from the pump to the tank.
- Remove the supply line from the pump head.
- If you hear air coming from the tank you have a bad check valve. If you do not hear air coming from the tank, you have a leaky pressure switch.
Problem:
My pressure switch is leaking. The small schrader valve attached to the switch leaks when the compressor cuts off.
Solution:
- Let your unit pump up.
- Turn it off.
- Find the supply line from the pump to the tank.
- Remove the supply line from the pump head.
- If you hear air coming from the tank you have a bad check valve. If you do not hear air coming from the tank, you have a leaky pressure switch.
Problem:
My compressor is not producing the air that it once did. It takes twice as long to pump up.
Solution:
- Replace your pressure gauge or check the tank pressure with another gauge to make sure that the gauge is accurate.
- Turn off your compressor or disconnect the power.
- Drain all of the air from your tank.
- Check your belt tension to make sure that there is no more than ½" deflection in your belt. (if your air compressor has a belt)
- Make sure that the motor pulley and flywheel are tight and not slipping on their respective shafts. (if your air compressor has a motor pulley and flywheel)
- Inspect your air filter to make sure that it is not obstructed.
- Remove the connector tube that sends air to the tank.
- Remove the check valve. It is located at the end of the supply tube towards the tank. Inspect for any obstructions in the check valve.
- Remove the head bolts on top of the pump.
- Remove the head off of your pump.
- Remove the valve plate off of your pump. It may be a one piece or a 2 piece design.
- Inspect the valve plate for broken reed valves or broken gaskets above or below the valve plate.
- This is probably your problem. Order the correct valve plate or gasket by manufacturer on the left category list.
- If you have an oil free, direct drive unit, inspect the piston ring and cylinder for wear or grooves on the cylinder wall. If you find deep grooves or a worn piston ring, you probably need to order a piston/cylinder kit.
Jul 22, 2021
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