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by Leon Thorp
(Sayre, pa)

My CAP60P ran perfectly until the other day. Now it will not get above 20psi and motor continues to run.

Cannot find any air leaks except one place but not sure what the function of the Rilsan tube is.

It is blowing air where it enters the pressure switch and if I recall it has always done this so I suspect it may be some kind of safety device.

Compressors 4 years old and only has about 4 hrs use. It has held the 20 lbs of pressure in the tank now for 24 hrs.


The Rilsan tube is a brand name flexible tube manufactured / supplied by mebraplastik.com .

On your compressor I suspect this tube runs from where the air line to the tank from the pump head reaches the tank, and the pressure switch?

Bostitich CAP60P compressor parts diagram
Bostitich CAP60P compressor parts diagram

That this has leaked all along might be a problem Leon.

If the air is blowing out of the unloader valve and not out of hole in the tube, then your tank check valve is leaking air out through the pressure switch, and that may have recently increased to the point where the compressor cannot overcome the leak.

If the air is actually blowing out of the tube itself, then I would surmise that the tube has failed.

First stop the air leak, and then, if the lack of pressure build continues, add a comment here and please add a photo of your compressor.

If you review the troubleshooting page you’ll see pages about why air compressors run but don’t build pressure.