Troubleshooting a "Skipping" Pump

When the fluid pump in an air-assisted airless rig loses pressure intermittently, clean out the ball check valve. July 27, 2008

I was spraying this morning to get a job out the door this week when my pump began to skip a beat. The spray would pause for a small portion of the pump cycle. I haven't encountered this maintenance issue with this unit and I'm wondering what I have to do to correct it the next time it happens. Is it something with the check balls at the bottom? I got the unit running again by blowing out all the paint and running thinner thru the lines.

Forum Responses
(Finishing Forum)
From contributor A:
Have you checked the filter at the gun?

From contributor B:
Here is your fix in less than fifteen minutes. Unscrew the black hose and above it there is a hex nut. You will find a ball check there. Clean it well. I'm ninety percent sure, you have junk in there, and the junk doesn't let the ball seat in the groove.

From contributor C:
I have found a clogged siphon tube and hose before. Sometimes a piece of the 5 gallon can gasket has gotten caught in the line.

From contributor D:
I agree with contributor B. This has happened to me numerous times. That's usually the culprit.

From the original questioner:
That's what it was, all right! Found a chip of wood. Imagine that, in a cabinet shop, no less. Thanks for the help, guys.

From contributor E:
To contributor B: Nice Tip! Darn those wood chips ;)