My stanley compressor will not shut off untill the safety pop off valve activates

I don't find that model in my database but if the safety valve is popping it is one of only a few issues:
1) The safety valve is weak or defective - run the compressor and watch the pressure gauge and see when it releases. Most compressors cycle on at around 90psi and off at around 120psi - the relief valve is usually set at 130-140psi. If it releases before 130psi I would replace the safety valve.
If it blows off above 130psi...
2) The pressure switch is defective if the unit doesn't shut down at it's labeled pressure (most are 120-125psi)
If it runs beyond the labeled pressure and blows off then replace the pressure switch.
3) If the unit has a pilot valve instead of a pressure switch and the unit builds up past the labeled pressure then you can follow these instructions to adjust https://www.youtube.com/watch?v=6CZ9Hznh6EI

If safety pressure release valve pops open then electric pressure switch is bad, however if compressure keeps running and never pops safety valve then most likely tubing / joint leaks or cylinder / ring worn out. Spray soapy water on all joints and drain valve , if no leaks suspect cylinder. Good luck

The pressure switch shuts the motor off when a designated pressure is reached. If you took that unit off then it wont shut off and builds pressure until the safety valve opens.

The pressure switch is either out of adjustment or has failed. The compressor should shut off at a much lower pressure than the safety valve (~100 psi)

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/dave_fb2c45146b845cea

The over-pressure relief valve may be defective if the valve is opening before the desired tank pressure is reached. If not, then the shut-off pressure adjustment (if there is one) may be set wrong. You'll need to find out from the manufacturer exactly what static tank pressure the compressor is designed to provide and then determine if it is working correctly. If so, then the relief valve might be defective. DO NOT attempt to defeat the relief valve under any circumstances - it can result in compressor damage or a dangerous tank failure.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/dave_fb2c45146b845cea

Take it back, and get a replacement, would think pressure control fault

Your problem dependents on when the safety valve is opening. If the safety valve is opening before the tank reaches its rated high pressure level, usually 130 to 150 psi, the spring in the valve is weak or broken; replace the safety valve. If the tank pressure is going over the rated high pressure level, the pressure switch isn't turning the motor off when it should; replace the pressure swtich.

The pressure switch (on / off switch) must be adjusted or has failed. A qualified Bostitch Technician can determine if the switch can be adjusted or must be replaced. Each model is different and without the model number I cannot give you a more precise answer.

The pilot valve (brass valve with flip lever or pull ring ) is what controls the pressure. The link below will help you adjust the pressure lower than safety valve release pressure (the safety valve has a rated value printed on side, make sure that the valve is actually releasing at stated pressure ). The pilot should be set to 135 ~ 90. A faulty safety valve will release pressure at lower that stated valve. Replace as needed. The link below is adjustment of a generic pilot valve, however the adjustment is the same on all brands of valves. Good luck

http://www.jaircompressors.com/jair/JAIR/techdocs/docs/PilotValveInstall.pdf

Hi
Perhaps the max psi of safety valve or safety valve is faulty .

cheers
John