Cat 3535 no pressure

[OurTown]

Our pump has zero pressure even though the motor kicks on and spins the pump up. This started a few days ago and the first thing I checked was the inlet mesh strainer. It had some restriction so I cleaned it and reinstalled it. The pump worked great for maybe 40 washes. Today it started again but this time after checking it the inlet screen was clean. I pulled the check valve on the outlet for operation and it seemed fine. The unloader had some rust and a little gunk in it and I cleaned that. Checked again and the pump still has no pressure. After pulling the 6 valves only one looked iffy but I doubt that is the issue. Since I had the valves out I checked the inlet water flow and it looks great. The belt seems tight as well. One clue that might help is that both times we had the issue is first thing in the morning after it sat all night. Is it possible the plunger seals in the head are bad? If there was a restriction after the pump would it build pressure or not? It seems like it would. There was no warning sounds before this happened. It either works and sound great or nothing.

 

[MEP001]

Usually the only way you wouldn't build pressure because of a restriction in the line would be if the pump has also completely lost prime. The first thing I'd do is pinch off the unloader's bypass line and see if there's any flow. Assuming it's truly an unloader, if there is no flow at all from the outlet, it will relieve all pressure on the pump with all the flow circulating through the bypass.

Is it dripping any water at all at any time from between the head and the crankcase? If the low pressure seals are worn, it can drain out and lose prime.

 

[OurTown]

I looked it up and this is what it is.


https://www.pwoutlet.com/PA-VS-200-180-HIGH-VOLUME-REGULATOR-p/8.712-753.0.htm


It is not leaking water anywhere. It has constant water supplied to to at all times so it doesn't seem like it could lose prime. I reassembled it and of course it works fine now. It does seem to take an extra second to get up to pressure but I'm being critical of it. Going forward I'm not sure what to do.

 

[OurTown]

After we got it running it had 21 washes before we left and was still working fine. My guess is that it will act up again after sitting overnight.

 

[MEP001]

I looked it up and this is what it is.


https://www.pwoutlet.com/PA-VS-200-180-HIGH-VOLUME-REGULATOR-p/8.712-753.0.htm

I hope you didn't pay $196 for that regulator:

General Pump CWR4525 Regulating Valve | Car Wash Equipment Parts | Kleen-Rite

The General Pump CWR4525 regulating valve is a great choice in busy in-bay automatic car washes!

www.kleen-ritecorp.com

 

[OurTown]

I hope you didn't pay $196 for that regulator:

General Pump CWR4525 Regulating Valve | Car Wash Equipment Parts | Kleen-Rite

The General Pump CWR4525 regulating valve is a great choice in busy in-bay automatic car washes!

www.kleen-ritecorp.com

It was on it when we bought the place. That General regulator has a grease fitting and makes me think that the one we have should be disassembled and lubed more often. If it was stuck in its resting position would it prevent the pump from getting up to pressure?

 

[MEP001]

I've been using the General Pump one for 25 years, and the only failure I've seen is that they eventually leak through the center of the adjuster when the o-rings fail.

 

[Waxman]

I had a low pressure situation on my CAT 3535 IBA. My problem was a solenoid valve inside the gantry on the high pressure line.

 

[OurTown]

I've been using the General Pump one for 25 years, and the only failure I've seen is that they eventually leak through the center of the adjuster when the o-rings fail.

How often are you supposed to grease them?

 

[OurTown]

I had a low pressure situation on my CAT 3535 IBA. My problem was a solenoid valve inside the gantry on the high pressure line.

Ours was a zero pressure situation. The pump only made a clicking noise and was smooth. I'm suspecting the pump seals or the regulator. 54 washes since we put it back together yesterday and still works great. I'm sure it didn't heal itself so it's just a matter of time before it happens again.

 

[Beddattery]

OurTown...

I have a WW Razor ver.3 and there are 3 of the old style regulators (NO grease fittings) on the pump stand.
WW recommends that you disassemble the regulator, clean and grease both the seat and o-ring on a quarterly basis.



Hope this helps...

 

[OurTown]

We had about 200 washes and it worked fine. Then we had a few days of bad weather and it sat. The first wash after that period the pump came up to pressure about halfway through the wash cycle but has not acted up since. After noticing that I disassembled the regulator and greased it. One thing that concerns me is that (now) the pump comes up to about 400 psi immediately and then after another second or so comes up to the set 1,100 psi. Still the question remains: Is it the pump seals or the regulator?

 

[Undertaker II]

We had about 200 washes and it worked fine. Then we had a few days of bad weather and it sat. The first wash after that period the pump came up to pressure about halfway through the wash cycle but has not acted up since. After noticing that I disassembled the regulator and greased it. One thing that concerns me is that (now) the pump comes up to about 400 psi immediately and then after another second or so comes up to the set 1,100 psi. Still the question remains: Is it the pump seals or the regulator?

Good Morning, Our Town. Not sure what machine your pump is hooked up to but I had a similar problem on a 4000. As I'm at my wash fairly early every day I noticed something similar on the first wash of the day and what it turned out to be was one of my Danfoss valves on my pump stand was leaking by with hot/warm water leading to the pump head of the cat pump and the temperature was just warm enough for the pump to falter. Once the incoming cold water got to the pump it picked up and ran fine the rest of the day. Hope this helps! Kevin

 

[OurTown]

Good Morning, Our Town. Not sure what machine your pump is hooked up to but I had a similar problem on a 4000. As I'm at my wash fairly early every day I noticed something similar on the first wash of the day and what it turned out to be was one of my Danfoss valves on my pump stand was leaking by with hot/warm water leading to the pump head of the cat pump and the temperature was just warm enough for the pump to falter. Once the incoming cold water got to the pump it picked up and ran fine the rest of the day. Hope this helps! Kevin

That's interesting but I wonder how hot did it got. Cat states these can run 160F water in the standard model without the high temp seals. This is a Super Wash fixed oval and I think it was made by Pro Equipment. I'm going to look into it further because it did it again this morning after having two bad weather no wash days.

 

[JGinther]

Maybe its neither the pump or regulator... Does your auto weep?

 

[OurTown]

Maybe its neither the pump or regulator... Does your auto weep?

No weep. It has a blow down system.

 

[JGinther]

Well, There's probably your problem. Time to check the check valves.

 

[OurTown]

Well, There's probably your problem. Time to check the check valves.

If it was stuck open then wouldn't it blow the air line? If it was stuck closed then it would not blow down which it does fine. There is another check valve that is right off the pump head and it was the first thing I checked. It does seem harder to push to open but it is much bigger than the small ones I'm used to. It did not seem like it was corroded or gummed up and snapped closed easily.

 

[JGinther]

I'm not talking about the check that protects the air line. I'm talking about one that prevents backward flow into the pump. I don't know what type of auto you have, but there could be a 'tank' style low pressure check valve between the pump and tank, or there could be one downstream of the pump. There could also not be one. In which case they are relying on the pump to be the check. However, the valves in pumps aren't bubble tight and slowly leak back from backpressure even when in new condition.

 

[OurTown]

I'm not talking about the check that protects the air line. I'm talking about one that prevents backward flow into the pump. I don't know what type of auto you have, but there could be a 'tank' style low pressure check valve between the pump and tank, or there could be one downstream of the pump. There could also not be one. In which case they are relying on the pump to be the check. However, the valves in pumps aren't bubble tight and slowly leak back from backpressure even when in new condition.

It is a Super Wash branded fixed oval made by Pro Equipment and it seems like a really simple machine. There is a check valve right off the pump head that should prevent back flow to the pump. There is no check valve between the pump and gravity tank. How much pressure would I have to exert on the 3/4" check valve off the head to get it to open? I removed it and put it on the bench and pressed the plunger with a screw driver. The spring seemed to take a fair amount of force to open it. I'm guessing between 10-20 pounds maybe but it is hard to judge.