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!
How To Get A Replacement Compressor Pump Gasket
If you are using industrial type air compressors, you can expect your compressor supplier to have a full range of spare parts for you, including any gaskets you may need.
This will likely not be the case for the lower cost, DIY type air compressors, that are being sold by the thousands from big and small box stores throughout North America (and the world??). What to do if you need a gasket?
Recognize first of all that a compressor pump head gets very, very hot in operation. Yes, you can burn skin with the heat generated, so any gasket material has to be heat resistant.
They acquired gasketing material. They disassembled the pump and located all the gaskets that were present. They then either removed them to use as a template to make new ones, or used the surface where the original gaskets were installed as a template, if the gasket was beyond removal in one piece. With the old gasket template as a guide, they marked the new gasket material appropriately, and cut the material to suit.
If your air compressor won’t build pressure past a certain point, the most frequent causes seem to be either the intake or high pressure reed / flapper valve is failing, or a gasket is letting go. You may, nor may not, be able to see the failure point if it is the gasket. Yet, once you have the pump apart, you might as well eliminate that as the potential problem, by installing new gaskets.
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.