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By: kenny Maldonado, colorado springs

I have a a Craftsman 5 gallon 1 horse direct drive oil lubricated cast cylinder air compressor.

I tried using two coil roofing nail guns on this compressor and now the thing doesn’t even build any pressure, I’ve checked the release valve it’s closed, exhaust seems to work right. What are your thoughts?


Why would you use two coil roofing nail guns on your poor compressor? What did it ever do to you? 🙂

Tried to find what model the 5 gallon Craftsman was, and didn’t find any of that tank size, so I guess yours has got some years on it?

Am I to understand that you have connected two air guns from the compressor discharge coupling, and neither gun is getting enough air to work?

There are many reasons why a compressor will run yet not build pressure in the tank. And if there’s no pressure in the tank, then the nail guns can’t run.

When the compressor shuts off (assuming it does) does air bleed out from the unloader valve constantly? That being the case, see the page about unloader valves on this site for help about that.

On the other hand, if your compressor is running continuously and not gathering any pressure in the tank, then it won’t ever reach cut out, and your unloader valve won’t ever open, so you have a different problem.

Rather than retype all the info already there, please visit the compressor troubleshooting pages about air compressors that run but don’t build pressure. The things you need to check are there. Please check them out and comment about what you found if you still need help.


Check your gaskets

– by: Anonymous

If your air compressor builds pressure to a point, and then won’t go any higher, check your gaskets. If you take the compressor apart, be prepared to replace the gaskets as they are brittle after use and most likely will tear.

Check the gasket that divides the chambers by the air intake. Make sure that there is no part of the divider gasket missing. Even a small gap can cause pressure to cease building.

You can buy replacement gaskets for most brands, or you can buy a sheet of gasket material at an auto parts store for under $10 and cut your own. Try to keep the old gaskets intact as much as possible to use them as a template.

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