# ProShot Fine Finish problem and solution



## mpminter (Mar 21, 2011)

I busted out the ol' proshot yesterday to paint a door, and almost immediately started having problems. The machine would cease to spray paint mid pass even though the motor continued to run, and I couldn't determine a reason. The material was SW ASE Acrylic high gloss and I knew the paint to be clean. The machine was clean and had been stored with mineral spirits in the fluid section and the tip and tip filter were clear. I called the Graco customer service department and the tech was very helpful. He was able to determine that my sprayer was losing prime and cavitating due to a loose seal. There is a plastic fitting that secures the suction tube to the inlet valve body, and it was no longer fitting snugly over the o-rings on the valve body. A few wraps of teflon tape around the o-rings and the problem was solved. I used the sprayer today to apply a second coat and didn't have a single problem. I thought I would pass this along in case anyone else has the same issue.


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## Ramsden Painting (Jul 17, 2011)

Thanks, we have had our issues with the Proshot but they took care of it also


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## DeanV (Apr 18, 2007)

mpminter said:


> I busted out the ol' proshot yesterday to paint a door, and almost immediately started having problems. The machine would cease to spray paint mid pass even though the motor continued to run, and I couldn't determine a reason. The material was SW ASE Acrylic high gloss and I knew the paint to be clean. The machine was clean and had been stored with mineral spirits in the fluid section and the tip and tip filter were clear. I called the Graco customer service department and the tech was very helpful. He was able to determine that my sprayer was losing prime and cavitating due to a loose seal. There is a plastic fitting that secures the suction tube to the inlet valve body, and it was no longer fitting snugly over the o-rings on the valve body. A few wraps of teflon tape around the o-rings and the problem was solved. I used the sprayer today to apply a second coat and didn't have a single problem. I thought I would pass this along in case anyone else has the same issue.


I had the exact same problem on the original proshot and the Graco rep told me it was impossible for mineral spirits to do that. He basically accused me of lying and said I must have used lacquer in it :no:


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## mpminter (Mar 21, 2011)

I'm actually kind of surprised that the mineral spirits would swell that plastic fitting. I have noticed that the suction tube itself has started to swell, but I guess I figured hard plastic would be more solvent resistant.


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