# Graco 795 problems



## Ramsey (Jan 15, 2011)

Ok so heres my problem. I have a Graco 795 with the auto clean. It's like 4 -5 hrs old. Digital screen. For pressure etc. Says is has 1004 gallons thru it. I dont see that but ok. 
The pressure builds up correctly but will not bypass. So wen I flip the switch to dump the pressure it continues to hold pressure as if I never flipped the bypass at all. Driving me nuts. Plus I would like to properly clean it . It has been sitting a wile but builds pressure and maintains pressure just fine. Weird as heck. So any suggestions ???
I have taken the bypass switch out to see if it's correctly movi g and it is operating fine but can't see In the brass to well so I don't k ow if it's clogged inside. Something tells me it has something to do with the auto clean feature. U put the gun to the stainless nut and tighten it on to a spring loaded valve. Well it doesn't work. It builds pressure but will not pass fluid thru it wen it's in auto clean. So it won't bypass that way either. It definately could be something sticking . Cus it wasnt very clean all this time sitting.I also took fluid section apart and cleaned ball bearing checked packings etc .it just won't dump the pressure. Hmmm 
Any suggestions guys ?


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## Wolfgang (Nov 16, 2008)

Mr. Fixit should have a couple possibilities for you. You can always PM him to get his attention.


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## Workaholic (Apr 17, 2007)

Sounds like the prime valve went bad. Mr. Fixit or NCPaint should chime in shortly.


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## Paradigmzz (May 5, 2010)

No prime, no play. Prime/spray valve all the way.


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## Ramsey (Jan 15, 2011)

The deal is that it holds pressure both ways and don't dump the pressure. Everytime I had a bad prime knob it usually seeped . That was my first intuition but it's a stumped for me. I've worked on alot of my sprayers and never had one keep it's pressure. Lol. I was actually concerned it may have to do with something gummed up in the auto clean section of the pump Cus I never had this happen.


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## mr.fixit (Aug 16, 2009)

If you have already removed the prime valve and the pressure will still not release then something in that housing where the prime valve screws in is clogged. release the pressure by the gun with the machine shut off if you have not already done so, remove the prime valve and lower the pressure control knob way down. start the machine and let it run but do not stand in front of the hole where the prime valve goes. if the housing is clogged it might blow free if not turn the pressure up a bit. dont go to high with the pressure. If that does not work release any pressure that may have built up by using the gun and remove the manifold filter cap and look inside to see if any of the orifices are clogged.It should not be the auto clean as it is down line from the prime valve. If that does not help you pm me and we can go further.


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## Ramsey (Jan 15, 2011)

Interesting. As I said. It's Ben sitting a wile. So at first it wouldnt build any pressure the I loosened the manifold filter and bam. It started shooting fluid so I hurried up tightened it back up and it built pressure fine after that but wouldn't prime. So u could be on to something with the manifold thing. I did clean the filter and holder but didn't pull the solid tube out. Does that solid stick if u may come out ?I mean it does have a hole in it so I assume the paint feeds thru their ? Then out the filter into the housing. Thanks


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## mr.fixit (Aug 16, 2009)

the material comes out of the fluid hose that comes from the pump goes into the manifold filter assembly and out the prime/drain hose until you close the prime valve which shuts the line off creating the pressure which is controlled by the transducer. If you are in the field and this happens you can get around this issue by using the gun as the drain tube. by that I mean if the drain hose is clogged you can hold the gun open until the spray hose starts to shake a little and when you release the gun it should pressurize. That is the way the original airless machines worked the prime valve is actually a safety valve as well and is set to open if your machine malfunctions and over pressurizes.


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## mr.fixit (Aug 16, 2009)

sorry it took me so long to answer I usually get on while I eat lunch but we are slammed with repairs and I have been staying after closing time so not to get to far behind on paperwork and I have been checking out the forum then also


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## Ramsey (Jan 15, 2011)

So I ended up using it on the job and it sprayed fine so I repacked it. Still never used the prime switch. Took the manifold part and found no clogs anywhere. It ha to be the bypass switch stuck in the closed position has to be ? So wen I have a switch I'll change it. Mr fixit. Wen u have a chance can u pm me I need a piston and a bypass for this thing. If u could send me the info IDE appreciate it thanks


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