100psi drop when gun is used...Cat/GinSan stand

[MDrost1]

Hello,

I know this is probably going to be simple, but I will still ask the question.

When I engage my SS weep gun the pressure drops from our target pressure of 1000psi to 900psi. Is this a gun issue? Is it a regulator issue? Any advice is appreciated!

 

[slash007]

One likely cause and the simplest to check is your spray tip. If it is worn, it will cause a drop in pressure. Replace that and see what you get.

 

[MEP001]

If the tip is eroded that much, the regulator won't be bypassing anything. The easiest test is to tie off the trigger and gently pinch the bypass hose with some needle-nose pliers. You should hear the flow as you're squeezing it if there is any at all, and if there's none it's either the tip or there's lost flow somewhere. Otherwise the regulator isn't working right.

 

[MDrost1]

New tip...nope
New gun...nope
Regulator seems to be working fine.
Any other thoughts?

 

[MDrost1]

Weep check valve good.

 

[MDrost1]

New regulator and bypass hose...pulling my hair out on this one. Thanks in advance!

 

[MEP001]

Did you test the bypass like I mentioned? If you're not getting flow through the hose with the trigger pulled, you're either losing flow through a bad check valve or there's a problem with the pump.

 

[MDrost1]

Yeah, I thought I did It correctly. I'll try again. The weep check is good. I did come to find this bay only has warm rinse water from the tank feeding all functions. Had never been an issue though.

 

[MDrost1]

MEP. Squeezed the bypass. No reaction in the pressure reading. I replaced the trough sfr a month and half ago. Thoughts? Thank you!

 

[DiamondWash]

How about seals on the pump head or the valves sticking?

 

[MDrost1]

I just pulled all the valves out and check them. All "O" rings a valves look good. I did put the old gun and tip back on, and I am up to 900psi from 750psi. Improvement but not perfect. Any other suggestions for places to look?

 

[cebo]

Am I missing something. You get a 100 psi drop from 1000 to 900. All my pumps have always done this. I run at 1100 psi and dial it up to about 1200 when the trigger is not pulled. Just have someone have the trigger pulled and adjust the bypasss up to your target pressure.

 

[MDrost1]

Nope, you are right on track. I am losing 100psi after the trigger is pulled. All of my other pump stand show 1000psi before and after the trigger is pulled. This one was fine for a long time as well. I take the drop in psi as a sign.....

 

[2Biz]

All regulators/unloaders are not the same, so they all may have different characteristics. When new, My Giant Pressure trapping unloaders don't vary more than 50psi when trigger is pulled or not. Over time the difference increases. When the difference reaches about 200 psi, for me its time to replace or rebuild the Regulator/Unloader.

 

[MEP001]

If pinching off the regulator bypass doesn't do anything, the regulator is NOT the problem. I'd start by checking the spot-free valve since it's the easiest thing, then that leaves only the seals in the pump. You're just not getting enough flow to the gun to reach 1000 PSI.

 

[MDrost1]

MEP001!
Just replaced the seal kit last night. I am back in business. 1000psi when gun is not engaged, and 1000psi when gun is engaged. Thanks. My first seal kit replacement. That was interesting. Thanks.

 

[DiamondWash]

Do I get a prize for having the correct answer???

 

[MDrost1]

Yup. A free car wash? . Jk. I appreciate your help!

 

[MEP001]

Do I get a prize for having the correct answer???

If there was a prize for the longest signature on this forum you'd certainly win that.