Compressor not building pressure and running funny.
by Andrew
(Temple City, CA)
I have a Craftsman 60-gallon 2 stage oil less compressor, model919.152811, which has a ac-0051 motor, and it does not want to build pressure.
I checked the valves and seals and all seem to be in fine condition.
While trying to troubleshoot it, I noticed that if I take off the inlet line from the pump into the compressor, the motor seems to run much better than with it hooked up.
We would like to get this working for some sandblasting but have so far been stumped by it not being able to build pressure.
Bill answers...
Hello Andrew. Welcome to the site and thanks for sending in your question.
That you notice an "improvement" in the running of the compressor when you removed the line from the tank may be significant, or it may not be.
If the line from the compressor head is open to atmosphere than there is no buildup of pressure in the tank, with the ensuing increasing load as the tank pressure builds.
On the other hand, it might mean too that the check valve going into the tank isn't functioning properly.
After you've read all of the questions and answers at the bottom of this page to glean new ideas, remove the check valve (it's normally installed where the line from the compressor head is ported into the tank) and clean it up. Replace it, and see if that makes any difference in the operation of the compressor.
Cheers,
Bill
