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I am having trouble with my company's Graco Xtreme 70:1 sprayer (pneumatic airless sprayer)

I have just cleaned the lower and replaced all the gaskets and o-rings. The pump seemed to work fine, but then after half an hour of work the piston started working like crazy, and the pressure in the pistol while painting was erratic - getting higher and lower from time to time without me changing anything.

The troubleshooting table I have from the manufacturer didn't help me at all. Nor did all the videos I watched online.
Think it could be due to icing, because the air from the compressor has been really humid lately. Then again, I just don't seem to find the solution.

Does anyone know what could be solution to my problem?
 

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I am having trouble with my company's Graco Xtreme 70:1 sprayer (pneumatic airless sprayer)

I have just cleaned the lower and replaced all the gaskets and o-rings. The pump seemed to work fine, but then after half an hour of work the piston started working like crazy, and the pressure in the pistol while painting was erratic - getting higher and lower from time to time without me changing anything.

The troubleshooting table I have from the manufacturer didn't help me at all. Nor did all the videos I watched online.
Think it could be due to icing, because the air from the compressor has been really humid lately. Then again, I just don't seem to find the solution.

Does anyone know what could be solution to my problem?
have you made sure the inline gun filter is not clogged up? This is the most common 'repair' I do on these air motor pumps.

It could be icing problem, to which there are several steps to remedy.. always check the simple stuff first.

 

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have you made sure the inline gun filter is not clogged up? This is the most common 'repair' I do on these air motor pumps.

It could be icing problem, to which there are several steps to remedy.. always check the simple stuff first.

Pretty sure that the filter is fine, but I am gonna check for that too, just in case. And all of that in the link above is worth trying.
Thanks for the tips:)
 

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Pretty sure that the filter is fine, but I am gonna check for that too, just in case. And all of that in the link above is worth trying.
Thanks for the tips:)
run the pump without the gun attached and watch the fluid output in relation to the piston, it can help diagnose issues including confirming the lines are not clogged up and you can get smooth fluid flow
 

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Did you get this worked out, and if so what did the problem end up being. We have a Titan 64:1 and were just having the same problem. Titan's answers were BS.
What material were you spraying, what size pump does it call for on the data page, and what was the temperature of the paint... and did you reduce it?
 

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I did install an after cooler (Compressor-after cooler-air receiver-airless spray), but the only difference I see is during really humid days. And icing was maybe just i small part of the problem here.

After a while I just took off the lower and dissembled it completely to take a look on every single part. It was all clean, but there were like 2 teflon gaskets missing (on the locations where they are supposed to be). I put the gaskets onto their location and added some extra teflon tape on all the threads ( inlet housing and filter housing) the to be sure there was no leak.
I also checked the the two balls (smaller and bigger one, i.e. ball piston and ball inlet), but they were fine, without any damage.
And finally, I was "playing" with the V-packing on the piston (5 gaskets on top of each other). In my case, I had to tighten the it little bit more.

Or to make a long story short, don't be sloppy while doing some basic maintenance :)
 

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Did you get this worked out, and if so what did the problem end up being. We have a Titan 64:1 and were just having the same problem. Titan's answers were BS.
What material were you spraying, what size pump does it call for on the data page, and what was the temperature of the paint... and did you reduce it?
I did get this worked out, but in my case it obviously not due to "too weak pump for this paint". We were spraying Sigmaguard 720 without any problems. the 70:1 ratio and 1/4" (150 feet I think) hose more than enough. We have even been spraying some solvent free paint with same pump and hose. We used a 521 spray tip (which is somewhere in the recommended range for this paint).

This particular paint is tricky, because it requires an induction time at lower lower temperatures (up to 25°C - 75°F). At higher temperatures we kept it in the shade, mixing only half a set and spayed it as fast as possible. On some hot days we would even put some ice around the mixed paint bucket. We learned this the harder way, because a few years ago, on a particular hot day the paint went from liquid to solid in 2 minutes. The hose was destroyed and the pump barely saved.

We measured the temperature of the mixed paint only a couple of times and it was pretty much the same as the surroundings. The air temperature (and surface temperature if the surface faces the sun) was the real problem.

Let us us know if some of this helped you?
 
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