What compressor pump gaskets do is separate elements in the pump to allow it to function properly.
The typical piston (reciprocating) compressor pump will have a pump air intake side and a pump pressure side. The intake side allows air into the cylinder on piston retract. When the piston cycles into the compression stroke the pressure side allows the pump to drive the air into the tank to increase tank pressure.
The gasket that separates these two halves on the pump head can be a robust one, or as is found in many smaller, low cost compressors, is not much more than a paper one.
One of the reasons why an air compressor will run, and not build pressure past a certain pressure level, which is displayed on the the compressor tank gauge, is that the gasket(s) in the pump head have failed.
Depending on the type of gasket failure, the result may be that almost no air is getting to the tank, or sometimes the compressor pump gaskets can contain air pressure up to a certain pressure level before the increasing pressure forces an opening.
If that gasket opening is to the outside of the pump, air will simply blow back out of the pump as the piston compresses the air, rather than flowing into the tank.
If the gasket weak spot is located between the high and low pressure side, instead of being compressed into the tank air will simply circulate back and forth between the low pressure side and and the high-pressure side. When that happens no further air is driven down into the tank. That is why the tank pressure reaches a pressure threshold and then rises no further, despite the compressor motor continuing to run.
In order to repair this sort of problem it is necessary to disassemble the pump and replace the gasket.
It is probably a good idea to try and obtain both the correct gasket kit for that compressor make and model, as well as a new valve plate. It is possible that a failing failed compressor pump gaskets symptom can be similar to that of a failed flapper valve in the valve plate. If it is necessary to tear down the pump to fix this problem, it might as well only be done once.
If you Google your compressor make and model, and typically trying to find parts without the model number will not provide results, you may find a number of sources or, you may not.
If there are no gaskets available for your make and model of air compressor, what is one to do? That’s the subject of this next page… how to get a replacement compressor pump gasket. We hope it helps!
Please leave us a comment if you have a compressor pump gasket issue that isn’t covered on this page, or the page about where to get one linked just above.