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dave defehr Posted: Jan 06, 2013 01:29 PM	pressure drop I have an E 10 with a fusion ap. The last time I sprayed poleurea, my B side pressures dropped about 3-400 psi as I pulled the trigger, then when I let off, pressures balanced out. I then cleaned out my 'A' side 'Y' strainer and there were little hardened iso chuncks. Could this be the reason for the pressure drop? I cleaned the 'A' side fluid section of the gun, so I doubt it was in there. Thanks for any help.
Mark Mouton Posted: Jan 06, 2013 03:37 PM	Usually, when you have a pressure drop, the side that is low has the dirty screen(filter), because the material can't move through it. It would probably be in order to clean the screens on gun and machine.
dave defehr Posted: Jan 06, 2013 06:17 PM	Thanks Billygoat jr. That's what I thought but my tech support told me it was the opposite which didn't make sense to me. I will clean machine filters and the entire fluid section of the gun and hope that will take care of this. Thanks for your reply.
clint moore Posted: Jan 07, 2013 02:06 PM	In most cases the side that drops is what material is coming out the gun and the side that maintains pressure is what is being restricted at the gun or hose end. High pressure = gun end, Low pressure = pump end.
Mark Mouton Posted: Jan 07, 2013 03:22 PM	I'm sorry I gave you the wrong answer. I always have to stop and think about what to do in the case you described. I was riding down the road and thought about the answer I gave and realized I was wrong and wanted to hurry and get home to respond and get it right. Maxx and your tech support gave the right answer. Also sometimes I have seen where the inlet of the mixing chamber gets partially clogged, usually on the A side, so cleaning the screens won't help if that's the case.
dave defehr Posted: Jan 08, 2013 10:17 PM	Thanks again guys, I completely cleaned the fluid section of the gun and did a spray test and all seems good. "B" still drops a bit, about 1 -200 psi from "A". Does this sound normal? I think it might be viscosity differences. Let me know what you think? Thanks again!
mason Posted: Jan 09, 2013 10:43 AM	Due to viscosity differences and sometimes just the gauge, you might have up to 200 lbs pressure difference between the A and the B side. The key is the foam and your pattern. If the foam and the pattern is good, keep on spraying.
dave defehr Posted: Jan 10, 2013 11:46 PM	Thanks Mason for your reply. I spray polyurea, but I do know what you mean about the pattern. When I pull the trigger I still get a nice round pattern, so as long as I have that I guess I'm ok. I'm still a newby when it comes to high pressure, I sprayed low pressure before.

Author

Comments

dave defehr

Posted: Jan 06, 2013 01:29 PM

pressure drop

I have an E 10 with a fusion ap. The last time I sprayed poleurea, my B side pressures dropped about 3-400 psi as I pulled the trigger, then when I let off, pressures balanced out. I then cleaned out my 'A' side 'Y' strainer and there were little hardened iso chuncks. Could this be the reason for the pressure drop? I cleaned the 'A' side fluid section of the gun, so I doubt it was in there. Thanks for any help.

Mark Mouton

Posted: Jan 06, 2013 03:37 PM

Usually, when you have a pressure drop, the side that is low has the dirty screen(filter), because the material can't move through it. It would probably be in order to clean the screens on gun and machine.

dave defehr

Posted: Jan 06, 2013 06:17 PM

Thanks Billygoat jr. That's what I thought but my tech support told me it was the opposite which didn't make sense to me. I will clean machine filters and the entire fluid section of the gun and hope that will take care of this. Thanks for your reply.

clint moore

Posted: Jan 07, 2013 02:06 PM

In most cases the side that drops is what material is coming out the gun and the side that maintains pressure is what is being restricted at the gun or hose end. High pressure = gun end, Low pressure = pump end.

Mark Mouton

Posted: Jan 07, 2013 03:22 PM

I'm sorry I gave you the wrong answer. I always have to stop and think about what to do in the case you described.
I was riding down the road and thought about the answer I gave and realized I was wrong and wanted to hurry and get home to respond and get it right. Maxx and your tech support gave the right answer.
Also sometimes I have seen where the inlet of the mixing chamber gets partially clogged, usually on the A side, so cleaning the screens won't help if that's the case.

dave defehr

Posted: Jan 08, 2013 10:17 PM

Thanks again guys, I completely cleaned the fluid section of the gun and did a spray test and all seems good. "B" still drops a bit, about 1 -200 psi from "A". Does this sound normal? I think it might be viscosity differences. Let me know what you think? Thanks again!

mason

Posted: Jan 09, 2013 10:43 AM

Due to viscosity differences and sometimes just the gauge, you might have up to 200 lbs pressure difference between the A and the B side. The key is the foam and your pattern. If the foam and the pattern is good, keep on spraying.

dave defehr

Posted: Jan 10, 2013 11:46 PM

Thanks Mason for your reply. I spray polyurea, but I do know what you mean about the pattern. When I pull the trigger I still get a nice round pattern, so as long as I have that I guess I'm ok. I'm still a newby when it comes to high pressure, I sprayed low pressure before.

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