Alltrade 19 will not build pressure over 60 psi
by Paul Pearson
(Salt Lake City)
I have a Alltrade 19 gal air compressor, I have checked out the following tasks.
I checked out the intake and I only have suction not pressure.
I disconnected the connection at the head side of the check valve under pressure and detected no pressure loss.
i could not detect any leakage from the unload valve.
this problem did start when I went to shut off the compressor at the pressure valve where it was hard to move the shut off. Is it possible that something broke in the valve and create this problem?? You help is appreciated.
Paul, re this: "I disconnected the connection at the head side of the check valve under pressure and detected no pressure loss." If you are referring to the tube from the cylinder head to the tank, with what did you determine that there was not pressure loss?
What I suspect is happening is that you have an internal gasket in the pump that leaks at 60 PSI and allows air to flow back and forth inside the pump rather than down to the tank.
60 PSI at the discharge line to the tank is quite a lot of pressure, and you likely, unless using some sort of instrument, couldn't tell if that pressure was 60 PSI or 120 PSI by feel.
So, even though it's putting 60 PSI into the tank, when that tank back pressure gets to that 60 PSI, I think you have a gasket letting go.