Wash Cycle Pressure Loss

[Randy]

I'd have to say your problem is in the high pressure system that go to the bay. Have you tried connecting the hose to another pump to see if you can get pressure on the line with that pump. When a check valve comes apart it can plug up the hose.If the pump runs with no flow it will damage the pump seals so the pump will pulsate. I've seen them get so hot the valve cage will melt.

 

[dbrown2911]

No I haven't tried that way. Maybe I'm burned out in thinking. But why would I get pressure with short hose right off of pump if it was bad? It pulsates without trigger pulled but when I pull trigger it is steady. That's the part that is throwing me off..I just don't have pressure when the original line is hooked up. I found the screw in the line from bad check and replaced check valve.. I have hooked up gun with short hose in almost every possible connection. I will make sure I swap hoses and try line with different pump..thanks everyone!!

 

[dbrown2911]

And also I did pull the head and changed seals but they looked fine.

 

[Randy]

Missing parts are not a good sign. You could have parts of the check lodged downstream of the manifold. Try flip - flopping the high pressure hoses from the next pump over to test the system going out to the bay. If it works on the other bay then you know it's not the out going hose. Then try putting the hose from the good bay on the bay that doesn't work.

 

[2Biz]

Went to attic took line off of manifold where all tubing ties in. Hooked gun up there before manifold and had pressure Took manifold down removed all 5 check valves and found one of them missing stop..replaced. Though for sure it was going to work... Nope still no pressure!!! Calling it a day.

IF you had pressure ahead of the manifold in the attic, At least one or more of the other checks is bad at the manifold. Did you try blowing back through each one? I bet if you pulled off all the lines to the manifold (Leaving the checks in place) and turning on the HP, you'll find the culpret!

IF there was blockage downstream of the manifold, the gage in the ER would still show pressure....You have to be loosing pressure at the manifold. AND its going somewhere....

 

[dbrown2911]

yes i did pull each individual check and blew through each one. They all seemed fine..except the one that was missing parts obviously. I will try the hose to another pump first (witch i think i did before but cant remember the results after tireless troubleshooting) then if it still doesnt work I will coupling around manifold to see if i gain pressure..thanks!! I will get back with results.

 

[cantbreak80]

Straighten me out on this…zero pressure on the gauge when the plumbing is in its normal configuration…and, zero or very little flow of water to the bay?

If this is true...and based on what you’ve reported, I would presume a plugged discharge after the attic manifold.

And why does the gauge go to zero? Likely because an “Unloader” is being used as a pressure regulator. If the pump’s high pressure outlet is plumbed THROUGH the regulating device, it’s an unloader and it’s doing it’s job…a deadheaded outlet causes it to “unload” all pressure back to the pump’s inlet…zero pressure.

If, on the other hand, the outlet is plumbed straight through a TEE with the regulating device connected to the branch of the tee, then it’s a regulator. A deadhead will cause the pressure to rise from its normal operating pressure.

If the equipment is a regulator, then you’re looking in the wrong place for a failed check valve…(OK, I’ve never seen a weep connection in the attic)…they’re usually on the bench plumbing, or on the wall.

Since pressure is created by the size of the spray tip, a wide open outlet (failed check valve) will cause the regulated pressure to drop to zero.

Hope you find it.

 

[MEP001]

I didn't think about an unloader causing a zero-pressure condition at the pump. That's about the only thing that makes sense at this point.

 

[Washmee]

I didn't think about an unloader causing a zero-pressure condition at the pump. That's about the only thing that makes sense at this point.

http://forum.autocareforum.com/showpost.php?p=74549&postcount=2

 

[2Biz]

Hmmm...I run giant unloaders and use weep guns. When you let off the trigger, pressure raises slightly on the gage. It does not go to "0". Somehow it keeps pressure against the HP line and the gage, but also bypasses about 90% of the flow back through the pump....

My unloader...

http://www.kleen-ritecorp.com/p-1961-giant-adjustable-unloader-1400-psi-13-gpm-yellow-springs.aspx


And the Mystery Continues!

 

[cantbreak80]

Install a fully closing trigger gun on it and see what happens...ok, don't. The weep guns work just like a spray tip, but with a smaller orifice. That's why the psi raises with the gun closes.

 

[Randy]

Hmmm...And the Mystery Continues!

I have to agree!!

 

[MEP001]

http://forum.autocareforum.com/showpost.php?p=74549&postcount=2

I don't know what you're trying to say with that. It seems you were suggesting the regulator/unloader is defective; I'm agreeing with someone saying that there could be complete blockage in the line and an unloader is properly doing its job.

 

[MEP001]

Hmmm...I run giant unloaders and use weep guns. When you let off the trigger, pressure raises slightly on the gage. It does not go to "0". Somehow it keeps pressure against the HP line and the gage, but also bypasses about 90% of the flow back through the pump....

My unloader...

http://www.kleen-ritecorp.com/p-1961-giant-adjustable-unloader-1400-psi-13-gpm-yellow-springs.aspx


And the Mystery Continues!

That seems like an awfully expensive and oversized unloader for a SS bay pump.

Unloaders function the same as a bypass regulator until the outlet flow is stopped completely, then it "unloads" the pressure from the pump to circulate with no resistance on the drive motor.

 

[2Biz]

I've had to replace 3 of them in the last 2 years. They ones I replaced looked like they were original. Probably 20 years old or older. They are $88 a piece...

How does this life expectancy compare to what you use? I know a lot of people use a bypassing regulator, but since this is how my stand is plumbed, I was doing good (at the time) to find the exact replacement and get them installed!

 

[dbrown2911]

well thanks for all the ideas..wasnt able to make it yesterday because when I was leaving my full time job at the school..my car decided to break a pully and snap my serpetine belt!? One of those weeks lol..but ok am going there today with a multiple of ideas to try and excited to find the outcome! Cant give this forum enough praise...IM IN LOVE! Thanks so much! I have only been in the biz since December but I have learned so much already!!

 

[MEP001]

I've had to replace 3 of them in the last 2 years. They ones I replaced looked like they were original. Probably 20 years old or older. They are $88 a piece...

How does this life expectancy compare to what you use?

I've replaced a couple, the rest are nine years old. Paraplate BR5-2, $55 last I checked.

 

[dbrown2911]

OK im back!! OK where to start... I went back to putting everything back in original place. Pump would not gain pressure..checked all check valves on manifold again and all seemed fine. I switched hose off of pump i thought was working fine and placed it on it and still nothing? I then put problem hose on "working pump" and still got nothing from the one that was working (this point im saying bad words) The new pump pressure regulator was getting warm and popping off the hose. Soooo..I took short hose off this pump with gun and all was fine. I then went out to working bay and switched guns and BAM the original pump i had working was back in service. ( i was troubleshooting with a gun that got a plugged up tip from the last day i checked it) During this the pump that hadn't been working..the pressure regulator didn't act the same as other..so i changed it out and problem fixed! So i had bad check valves in manifold in attic..bad pressure regulator on pump and plugged up tip on gun i was trying to troubleshoot with!! WOW!!

 

[I.B. Washincars]

Take that regulator apart. I'll bet that you find the source for the things lodged in that gun and probably that check valve.

Didn't someone mention a plugged tip

 

[2Biz]

Take that regulator apart. I'll bet that you find the source for the things lodged in that gun and probably that check valve.

Didn't someone mention a plugged tip

All this and you diagnosed it in 2 words! You're a Genius!