I have the engine of a refrigerator brand inelro 1/5 clutch engine check its pressure in high rises up to 450 psi but in 20 minutes it drops to 100 psi I think it does not go anymore can someone advise me ????

Good afternoon, I think it is not bad, the bad thing is that the needle drops suddenly to 0 psi, months ago I installed a motocompressor that exceeded 400 psi but in less than 1 minute I lost the pressure, logically I had an internal problem but the client did not have Money to buy another unit, I informed him that it was a risk to install it but he said yes, we installed it and it is working perfectly, of course, it is not something I recommend but your compressor for me will be excellent.