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Pulsating pump issue

wyatt

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I've been having some issues with two of my self serve bays pulsating on high pressure. It will hold pressure and then out of nowhere drop pressure, sputter and then build pressure and be fine for another minute or two. It has been this way ever since I bought the wash.

First thought was the seals in my pump were bad (giant pump). I decided it was time to get new pumps anyways and switched all 6 bays to cats. The same two bays sputter.

Second thought was they were being starved for water, so I replaced the plumbing from the water supply to the pump just incase there was corrosion or something in a fitting that was restricting flow. The same issue is persisting...

Any other ideas?
 

mac

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Well that is a good one. We know it’s not the pump so it has to be something with the water supply. Sounds like air is getting in to them. Could be air being sucked in through a fitting for the soap or wax. Or maybe the weep supply if you have that.
 

cooll903

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Well that is a good one. We know it’s not the pump so it has to be something with the water supply. Sounds like air is getting in to them. Could be air being sucked in through a fitting for the soap or wax. Or maybe the weep supply if you have that.
It is most likely this or it could be the puslastion dampeners are going out
 

mac

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Don’t think it’s the pulse dampners. Most systems don’t even have them anymore.
 

MEP001

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Pulsation dampeners are only there to smooth the normal vibration of a pump. There is no way a bad one will cause an issue like this.

There's probably a pocket of air building somewhere in the inlet plumbing that eventually gets to the pump.
 

wyatt

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I will try to remember to get some pictures for you guys. Thanks
 

Greg_T

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Not sure if this is your particular issue, but I recently had a problem with pump "pulsation" on two particular settings - high pressure soap and wax rinse. After some head scratching, I found a brass fitting on the pump inlet that was cracked through. Currently awaiting some stainless steel fittings to replace the brass fittings on all our 3 bays. It appears that when running high pressure soap or wax rinse, it would suck some air into the pump inlet and the pump would cavitate.

Hope you can find your particular issue soon.
 
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