Problem with Pump

[MarkAllen]

I've got a Cat 310 pump and it is a pretty new pump (I believe about 1 1/2 years old) and a month ago the key came out from in between the pulley and the pump shaft. I don't know how many times it ran like that or for how long each time but I know the pulley was ruined because of it. Well I replaced the pulley but ever since then it just doesn't seem like it is running right. It just sort of pulsates while it is running. I changed out the input valve to make sure it wasn't starving for water but it still pulsates. Surely the pump is not gone...right?

Could the problem be where I positioned the pulley back onto the pump? Maybe it is not exactly where it needs to be. How exact do you have to be when alligning the pulleys on the pump and the motor? It looks straight to the naked eye.

Ya'll remember I just recently bought my SS car wash.

 

[mac]

If it looks eyeball straight, it's probably OK in taht regard. The pulsation is caused by another issue. Most likely a valve in the head is bad. They are easy to remove and inspect. You can go to Cat's web site and get opening and inspection info. When they pulsate, you want to correct it pretty quickly or it can trash itself.

 

[phred113]

My experience with this pump and that problem is 1 of three things: 1) trash in a pump valve, 2) washout in the valve or seal area, 3) broken/damaged poppet. The 5CPs have a reputation for broken poppets from lot to lot, but the 310 is usually trouble free except for the washout issue. It may possibly be your plumbing if this was reconnected during the repair.

 

[MarkAllen]

My experience with this pump and that problem is 1 of three things: 1) trash in a pump valve, 2) washout in the valve or seal area, 3) broken/damaged poppet. The 5CPs have a reputation for broken poppets from lot to lot, but the 310 is usually trouble free except for the washout issue. It may possibly be your plumbing if this was reconnected during the repair.

I hate to ask a dumb question but as I said before I am new to the business and have never "had the privaledge" yet, to take one of these pumps apart but what is a poppet? And I've heard the term "washout" used several times on this forum but I'm not really up on all of the car wash lingo. I have an idea of what it means but not absolutely certain of what you guys are referring to when you use that terminolgy. Can you explain?

 

[phred113]

Well, welcome to the world of car wash - you are living the dream now!
The poppet is an old school word for the valve disc or the thing the spring pushes down inside the valve. Valves have seats, poppets (discs), springs and cages.
Washout describes the erosion of material in the head - usually the seal area and valve bores. If the rubber seal or o-ring cannot contact the brass head then fluid leaks by. This seems to be an issue with this model of Cat pump. Others can come along and answer more.

 

[MEP001]

All pumps experience washout. Your problem is hopefully simpler than that.

1 1/2 years old is irrelevant to wear - the amount of use is what determines how long the parts will last.

Order valve o-rings, back-up rings (6 each), a valve kit, a seal kit and at least one seal retainer, then start checking things. The most common problems that cause pulsating are in the valves, and is easily checked. Remove them, check the o-rings and back-up rings, replace them if any are cut, missing or look extruded. Check them carefully by looking in the bottom for debris, and check for a proper seal by sucking on them. A small amount of air through is normal, but a lot indicates debris or a bad poppet. If you find a problem, coat the o-rings with Hylomar and reassemble. If not, remove the head and inspect/replace the seals.

 

[Wally]

If you are picking up air it will pulsate also. Tighten all the lines that lead to the pump, soap, wax, inlet water.