Weep check valve...no, not that one.

[I.B. Washincars]

I have trouble with weep backing through my pumps and overflowing my rinse tank, so I have to have a check valve just after the pump outlet. I've tried several. They seem to initially work, but in no time I'm overflowing again. Virtually everything listed states "Low cracking pressure" or something along those lines. I think that is the crux of my issue, the weep not having enough pressure to make it seal reliably. I think I need something with a high cracking pressure, but that seems to be a national secret. Any suggestions on what to use in this application? The plumbing is 3/8".

 

[2Biz]

Have you tried this one?

https://www.kleen-ritecorp.com/p-3247-kleen-rite-check-valve-38-f-ss.aspx

Its not cheap but is rebuildable. I purchased 8 of these a few years ago for when my giant unloaders fail and will switch to a regulator. Seen several manufacturers that used them and also was what CB80 recommended. He said he had these in his setup and some are 20+ years old and never an issue. Just a simple "O" ring seat....Glad I got mine when I did...I think I paid a little over $20 ea. Now they are $40!

 

[JGinther]

Those used to be good, but I personally believe they now suck. I have had so many failures of those that I went searching too. But the old ones - still working just fine! I bet most of the issue would go away if you oversize to half inch valves. The flow rate through the check valve along with the pulsation is tough on springs and the retaining parts. Crack pressure is in the direction of flow, so I don't think that is related to your issue. The spring should be keeping the valve closed and the weep should just keep it there (I'm talking about the check valve on the outlet of the pump, not the one preventing high pressure from entering the weep plumbing - that one would need to be a low crack type).

 

[I.B. Washincars]

Crack pressure is in the direction of flow, so I don't think that is related to your issue.

My thinking is that with a low cracking pressure the valve is not tightly shut off. The weep pressure isn't much to begin with and most of that is going out to the bay. I'm thinking it's getting by the check because of not a very positive shutoff. Is my thinking off-base?

No 2Biz, I haven't tried that one. I have tried three different ones. Two leak and the other would come apart and it's guts would stop flow downstream.

 

[slash007]

My thinking is that with a low cracking pressure the valve is not tightly shut off. The weep pressure isn't much to begin with and most of that is going out to the bay. I'm thinking it's getting by the check because of not a very positive shutoff. Is my thinking off-base?

No 2Biz, I haven't tried that one. I have tried three different ones. Two leak and the other would come apart and it's guts would stop flow downstream.

I've had the same exact issue and you only notice in the winter since the weep is low pressure. I had good luck with Fluid Control CV's, but then had a batch that all leaked. I've since used the one's from KR that 2biz posted and so far so good. I have them on top of each boom to inject air so that the water doesn't keep running in the bay after being used and when the weep is on, I will notice water leaking out of the top of the CV on so many brands.

 

[copperglobe]

I had the exact same thing happen to one of my washes this winter with the start of weeping. I kept getting my wax tank diluted- water flowing back into that tank diluting the wax. Turned out to be a bad wax solenoid valve in one of the bays. My rinse tank is only hot water used with HP soap and HP wax. My "rinse" is cold city pressure direct through a solenoid valve into the pump. Maybe my setup and problem doesn't help in your case.

 

[Jeff_L]

Don’t know enough about your setup, could be a check or what copperglobe stated. With so many of each, might just have to go through a process of elimination. Pull the hose feeding your rinse tank that is flowing backwards, turn on the weep, watch the back flow, and start eliminating components.

Probably an easier way to do this, but I enjoy the exercise of running up and down the attic stairs lol. Of course, probably shouldn’t do it when the temps are below freezing.

 

[I.B. Washincars]

I already know where the problem is, I just need a more reliable check valve. I can replace the check and it will fix it, for a while. I just don't think I'm using the best valve for the application and am trying to figure out which one is.

 

[Jeff_L]

Spring should be keeping it closed, even if you’re putting a new one in it shouldn’t go bad that soon. Perhaps there’s pressure on the input side keeping it open such as a solenoid valve upstream leaking. Just grasping at straws here, I know you’ve been around awhile and know what you’re doing. Just tossing thoughts onto the table.

 

[2Biz]

IB, I'm sure you are well aware that the original Mark VII Giant Unloader had a "Hidden" check valve to keep weep from back-flowing. I think you were the one who told me about it. Drove me nuts in the beginning. The check in the unloader is brass and uses an oring to seal. I've got some unloaders that I changed out in 2011 and the weep check is still doing its job. The SS check I linked to is set up the same way using an oring. Only difference is its SS. I know the SS check expensive, but I like the part about it being rebuildable, cheap! If it were me, I'd give one a try. I am when my Giants start to fail.

 

[PaulLovesJamie]

I also T my weep in after the pump outlet, through this fluid controls check valve https://www.kleen-ritecorp.com/p-1768-fluid-controls-check-valve-38-f-x-f-stainless-steel.aspx
Been that way for over 20 years, I put a rebuild kit into them when I do any major work on a pump, maybe every 6-8-10 years? I rarely have a problem with this setup.

FYI, I do tend to run my weep at a little bit higher pressure (closed recycled system so water cost is not an issue). Cant tell you what pressure because the gauge hasnt worked right since the entire wash froze up on me 15 years or so ago. Coincidentally I ordered new gauges 2 days ago, so I can tell you the pressure in a couple days if you want.

 

[I.B. Washincars]

Keep in mind that this is not happening on one bay at one wash. I have three washes with Mark VII gravity fed systems. It happens at all of them. One wash has the Giant unloaders, the others have MV 580 I believe.

 

[Car_Wash_Guy]

I have the same problem. I found faulty check valves coming out of the rinse tank and thought I found my problem. Replaced with 3/4" Fluid Controls CV's and still have the problem but less severe. I might have gotten 1-2 bad ones ( 1 confirmed ). I always five them a good "blow" check to ensure they are restricting back flow but I give up...

 

[JGinther]

I have tried three different ones. Two leak and the other would come apart and it's guts would stop flow downstream.

That's why I think flow rate is the root of the issue here. I think two bushings sizing up to 1/2" or 3/4" will make all the valve types viable again. The problem we had with the 'rego' check valves was the o-ring seal pushed sideways halfway down stream - probably related to flow rate also. Others may not be having the same problem because they use a smaller tip in the bay or operate at a lower pressure. Or possibly the manufacturers just don't make them like they used to! I don't really care if a check valve is rebuildable... I just want it to work as close to forever as possible.

 

[2Biz]

I'm having a hard time figuring out what can come apart in this CV and lodge itself down-stream. Even if the o'ring broke, I don't think there is not enough clearance for the o'ring to make it past the center section of the stem. Flow pushes towards the spring....Thoughts? I still think its a well built CV.

 

[I.B. Washincars]

I also T my weep in after the pump outlet, through this fluid controls check valve https://www.kleen-ritecorp.com/p-176...ess-steel.aspx

The weep doesn't go through the valve I'm having trouble with. The HP goes through it and weep is tee'd in downstream. Although, the valve you list does look like the one that I have had break apart and plug plumbing.

2Biz, I've not used the valve in your picture.

 

[2Biz]

It's the "Rego" KR rebranded one I linked to in the 2nd post in this thread.

 

[JGinther]

I'm having a hard time figuring out what can come apart in this CV and lodge itself down-stream. Even if the o'ring broke, I don't think there is not enough clearance for the o'ring to make it past the center section of the stem. Flow pushes towards the spring....Thoughts? I still think its a well built CV.

All 20 or so that I have had fail all had the same thing... The o-ring halfway rolled outside of its seat - stretched - and then got sandwiched holding the stem at an angle and then allowing flow both ways.

 

[MEP001]

Try the Fluid Controls check valve with the Teflon seal. You may have to go to 1/2" - I had the same issue using a 1/4" on the high-pressure spot free to the bays, the flow was too much and it broke off the plastic bits that hold the poppet/seal/spring in place and it wedged in the fitting. I replaced it with 3/8" and it's been fine. The Teflon seal won't come off the poppet like the o-ring will.

 

[2Biz]

Interesting discussion! Just wondering why some operators have very good luck with the Rego and some not so good? Some old threads listed below raving about how good they are...None as to how bad they are until now.....

https://www.autocareforum.com/showt...nd-Ball-Diaphragm-Check-Valves&highlight=rego

https://www.autocareforum.com/showthread.php?9727-Best-Check-Valve&highlight=rego

Here is a photo of the Guts of the Giant unloaders I currently use that were standard on the old Mark VII stands. The small brass stem/o'ring and spring is the back-flow CV to keep weep from flowing back into the gravity tanks. Its a lot less substantial than the Rego and I've never had an o'ring fail on the Giants to the point it came off the stem. They just leak by when they start to fail. I can't remember the last time I had issues with float tanks over flowing. But now know when it happens, this is the culprit...