I have a sears craftsman air compressor. It runs fine until it builds gets up to the max air pressure. It shuts off then as it should but as I use it and the air drops and it tries to restart, it barley turns over then it pops the circut breaker. It is a 33 gal horizontal model. I am not sure of the model #. I could get it if needed. Al F

maybe you are reading the gauge wrong
the tank gauge and the regulator gauge will read the same but the gauge that reads when you adjust the regulator is the out line pressure to be n maintained during tool use

most likely a problem reed /poppet valve in the compressor heads

It will leak until head pressure is drained. I'd it keeps bleeding until late no more air in than your tank check is bad

My compressor runs for about 5 min and shuts off.....does any one knows what could be the problem?

thanks

The problem with compressors not building pressure is usually a bad pressure switch or bad regulator. Does the motor shut off at 20psi or does it continue running and not build pressure? If the motor continues to run with no increase in pressure, the you should go over the machine looking for air leaks from your regulator back all the way to the motor. Any air leak while the compressor is running can cause the pressure to "peak" way before the intended shutoff that it is regulated to.

IT depends on the tool. Some tools require higher cfm. (cubic feet per minute) of air. IF your air line is not large enough, then sometimes 90psi is not enough to operate a tool as there is a pressure drop at the tool. Look at the required cfm for each tool. Find a chart for air line size, cfm and pressure. Most impact wrenches should be used on a minimum 3/8" air hose. You could look at your manual and see what the max pressure is on your compressor. You may be able to decrease the differential pressure e.g off and 100 and on at 90, but then the compressor will cycle more frequently, and may exceed the duty rating of the compressor.

The compressor will not auto shut off until it reaches the preset pressure which is usually around 100-130 psi - your problem is leakage of air from the oil filler cap suggesting that you have a failed internal valve.

It sounds like it is not getting enough electricity.
Try plugging in to an outlet on its own circuit without an extension cord. make sure the circuit is rated for your air compressor. If it is on a circuit with other appliances, refrigerator, lights, ect. try shutting them all off before turning on the air compressor.


Good luck

Yes,but if the max is 125 you don't want to increase it above 110 and set off the pressure relief valve.

your max pressure switch is faulty, and shutting off the power early. replace switch, check owners manual for location(should be near power wires)