Cat 310 pump manifold washed out?

[Keith Baker]

How can you tell when a Cat 310 manifold is washed out? Where does it wear?

I have a pump that dropped in pressure to 800 PSI and the hose is pulsing badly. The high pressure seals looked bad, so I changed all of the seals. I still had the same problem. I inspected the valves and they all looked good, but I don?t have any new valves in stock. I?m going to get new valves, but I want to check the manifold when I get back to it.

It?s not sucking air like it does when the low pressure seals are bad, and there?s no water leaking under the pump. Is just has low pressure and a pulsing hose.

Thanks:

Keith

 

[ncwg]

i seem to be having the same problem, hope to see a response!

 

[washnvac]

Does the pump have full pressure when the trigger is not squeezed? (by pass mode) If it does, the pump is probably starving for water. Check your incoming line and your inlet check valve, also the regulator. I have had quite a few springs on the checks corroding a bit, then it will not fully open. I always put a new inlet hose on with a new check valve. If the pump does not have pressure in by pass mode, most likely the head is washed out.

 

[Jim L.]

Keith

My washouts occurred in the valve area where the valve o-ring contacts the seat. Remove the valve and you should see where water has bypassed the o-ring and eroded the brass seat area. My cure was to order one new CAT 310S pump (the S means stainless steel sleeves in the valve and seal areas). I then took the old head and sent it to Kansas (http://www.dynajet.com/html/order.html) and had them rework it with stainless sleeves for the 6 valves and 3 seal areas. The price was about $150. I then waited for the next pump to wash out. In 9+ years I’ve done all except one of my 310’s. No problems once you put the stainless to them.

 

[I.B. Washincars]

They also erode in the HP seal area. Usually you can look at the outsides of the seals and see where water has been bypassing. Look at the adjacent area in the manifold and see if it is eroded. Once you see a washed out manifold you won't have any trouble finding the next one. IMO, it is not cost effective to sleeve the head. By the time you pay for the repair, shipping both ways, and a seal kit, you are way over 200 bucks. That's too much to sink into an old pump when there are brand new pumps available for less than $400.

 

[MEP001]

You shouldn't have to replace the valves unless there's an obvious problem. Pull them back out and replace the o-rings and back-up rings if they look worn, flattened or extruded. Visually inspect the poppets of the valves (they sometimes crack) and look for debris holding them open or blocking the flow. I've had check valve o-rings break loose and end up blocking the flow almost completely. The best test for the valves is to suck on them. A tiny amount of air is normal; ideally they will seat 100%, and it should be somewhat difficult to blow through them.

A manifold that's eroded in the valve o-ring area will usually have the o-ring blow out again in a short time. You should be able to see it with a flashlight - it will look like a tiny canyon eroded into the brass. I have some good photos of what to look for, but I can't find them right now. They're probably still on my old, old computer that won't boot anymore.

 

[MEP001]

Jim L., are you certain they sleeve the valves as well? I haven't been able to get hold of someone to answer that question, and I wouldn't waste the money on it if they don't.

Pat, I would think that it would be cost-effective in the long run. The parts should last longer, and assuming the repair holds up the manifold will never wear out. Yes, you can get a new pump for $400 (or a new Cat for $550), but that new pump has the same potential to wash out, then it's another $400, then another. In 4 1/2 years I've already replaced 4 of the 6 original 5CP manifolds (fortunately under warranty) and another is beginning to go through valve o-rings too quickly. I've switched one out to General, but I don't know if that was a good idea.

 

[mjwalsh]

It?s not sucking air like it does when the low pressure seals are bad, and there?s no water leaking under the pump. Is just has low pressure and a pulsing hose.

Keith

Keith & ncwg,

We put new seal kits in one of our Cat 310s & it still would not work. We checked & checked for any potiential air leaks. None. OK, we then put a known good spare pump on. Still same problem like you two describe.

Guess what, this morning we took the 2 garden hose faucet washers off of the inlet hose & put new ones on even though the the existing looked OK & did not show any signs of leaking. Lo & behold, that turned out to be the problem. The moral of the true story is that air leaks can be VERY TRICKY. The pump is finally back to working properly.

 

[Keith Baker]

Thanks Washinvac, you sent me in the right direction.
The inlet strainer was partly plugged. It looked like calcium from hard water had covered the screen area. I had a problem with the water softener last fall, and put a new one in.
I checked the other 5 strainers and they all had some buildup, but not as much as the one that was starving the pump.
Thanks to all who responded.

Keith

 

[mjwalsh]

ncwg,

How did you solve your polsation & lower pressure problem on your Cat 310???

 

[washnvac]

No problem Keith. I have always learned to check the very easy stuff first. Pulling that pump head is the last resort. I have found 80% of the time it is that check valve or the inlet hose is sucking itself inward.

Regards
Brian Dayton

 

[ncwg]

my cat 310 just keeps going through the o rings so i just keep replacing them, always have to replace the same one, though it will last about a month at the most. So i guess that is cheaper than a new pump, still new to all this.

 

[washnvac]

If you are talking valve o-rings, that is normally a simptom of head wash out. I think the last one I sent to Kleen-Rite was about $180 for s/s sleeve insertion. That is a fairly permanent fix. In my opinion it is worth it to send the head for repair.

 

[Jim L.]

Jim L., are you certain they sleeve the valves as well? I haven't been able to get hold of someone to answer that question, and I wouldn't waste the money on it if they don't.

MEP

I checked this morning on the head I have on the shelf. It has 9 new stainless sleeves in it.

 

[mjwalsh]

direct city water test

What I can't figure out is that I thought I read on a previous post that a fool proof way to determine if it is an air leak problem is to put 50 lbs of pressure(city water in our case) directly on the Cat 310 inlet. I did that with a plugged soap inlet & it still pulsated. It was only after I changed the inlet hose washers that it started working without pulsation.

 

[MEP001]

Thanks, Jim, I've got a 310 head lying around that I'll send off. Eventually I may send off some 5CPs if they'll do them too.

 

[mjwalsh]

I wonder how many of us use a stainless spring inside the inlet suction hose. Mine are still in there from the original Specialty Equipment install. It does seem like a good safety precaution in case the rubber starts getting softer with age to prevent an inward collapse factor. It would be nice to find out the success rate of using the city water pressure to rule out the possibility of an air leak.

 

[MEP001]

I've never used one, but with my setup there's no risk of the hose collapsing since there's no suction on it.

 

[Randy]

In the 26 years I've been in the car wash business I've never experienced a head wash out problem at my wash. I attribute this to feeding the pumps with reduced city water pressure. I?ve replaced a lot of pump heads on equipment that are fed with gravity fed tanks. I?ll look around and see if I can find a washed head and take some pictures of what it looks like for those who have never seen what a washed out head looks like.