I have a ingersoll rand t30 air compressor model #5HN1.\r\nthe problem im having is when the air tank has above 100 psi the electric motor struggels to turn the compressor and keeps blowins curciut braker. when i release the the air from the tank to around 50 psi the motor starts fine, i think it has a stuck check valve but i dont know where it is located.can someone help

SOURCE: Air Compressor, low pressure

does the compressor keep running all the time but never gets above 40 or does it turn off at 40?
if it is turning off at 40 I would try using another gauge just to be sure it is 40psi, and if that is the case then you probably have a faulty pressure switch, if the compressor is constantly runnign but won't get past the 40psi then you may have a worn out compressor, check the oil for either a low level or if the oil is dirty, if it is you may just need to drain and refill but if that doesn't fix the issue then you will need to rebuild the compressor

SOURCE: Ingersol T30 won't shut off and blows pressure release valve

the wire juction box on your compressor has a pressure switch that may be wound in to tight take the cover off the box there should be a switch with a machine screw with nut and washer and spring back this nut off and see if that helps if you go to far you just crank it back in until the switch hit although it may be the other way around you may have to tighten to lower the pressure some of them are made that way if this does not solve your problem send me a picture of the switch and can solve it from there

SOURCE: I need the head bolts torque specs for an

With Graphite gaskets the torque is 34 lbs.

SOURCE: How do I adjust shut off pressure on an Ingersoll

The best way to go about the task of adjusting the pressure switch is to remove the cover to switch and note the brand/model number. Sometimes instruction are under cover of switch. With switch information, look for mfg. instructions. You will most likely see one or two springs with lock nuts. Do not turn them yet. Most pressure switches are sold with factory adjustment and are sold in pressure ranges. For two stage compressors as yours, the pressure is usually factory set at much higher (150-175) pressures than single stage which is usually about 120 -125. If you change the pressure setting it will also change the differential cut on pressure. The factory will actually use different springs to achieve desired pressures and are color coded. There are too many different brands of switches to recommend how to change pressure setting. You may discover that you can only change the pressure just a small amount (+or -15-20psi ). If you find the information about your switch, make sure that you count the turns exactly so that you can return to factory settings if things go wrong. You can extend the life of the comperssor by lowering the pressure as more amperage /heat is produced to achieve higher pressures. Good luck