Cat 3535 Question

[washtubman]

One of my IBA 3535 pumps will only get up to 900 psi and even at that pressure, it sounds like it is working harder than the other one at 1100 psi. I have taken all the valves and low and high pressure seals out of the head and everything appears to be in good shape. There is no water in the oil and there is no cavitation from starvation, etc. The regulator is set about as high as it will go and if I turn it in further, I can get a bit more pressure but the pump really struggles. Pistons look good also. Ideas or other things to look for would be appreciated.

 

[Washmee]

Drive belt slipping, or inlet screen clogged.

 

[whitescout]

Does this auto get used more than the other? How do the nozzles compare? If the nozzles are worn, they are not creating the same restriction, and will not be able to produce the same pressure.

 

[washtubman]

This one actually gets used less and the tips were just changed a month ago. Inlet screen is clear and belt is tight. Could it be the regulator? I'm going to switch regulators from the other one and see what it does.

 

[MEP001]

A bad regulator won't cause it to sound like it's struggling - it will either leak or it will just bypass too much water and not allow it to build the pressure you want.

 

[Reds]

are all of your functions working? Could a solenoid be stuck shut and the pump deadheading? I would try swapping the regulator and guage first. Perhaps the pump is cavitating - is the ball valve in the inlet line adjusted properly? Could the motor have something wrong with it causing it to run at a lower rpm? Maybe a voltage check to make sure all 3 legs on the motor have full power? I'm not any good with electric/electronics problems but I know that there is a way to check the motor with a guage.

 

[helpfuljames]

Make sure your gauge is on the pump head not further down the plumbing. You could have something collapsed or restricted between the pump and gauge so the true head pressure is not measured. This issue is common in cleaning machines that have heaters. (I know yours does not) The heater provides a much greater restriction than expected and the pressure going out (where the gauge is) is less than coming in.

 

[Buzzie8]

Any update on this washtub man? I am havingbthe same problem with one of my IBA's. I am going to troubleshoot tomorrow.

 

[washtubman]

After trying the obvious; switching regulators, checking belt, gauge, etc., I guess I'll order the high pressure rebuild kit. The parts look good, but it is quite old, so may as well rebuild while I have it off. It's an 88 model, and they have changed the high pressure configuration on the newer models, so I don't know if I'll have to get the newer type parts or not. Anyone know? Also, is Kleen Rite the best price for this stuff?

 

[MEP001]

Check with a Cat distributor and they can tell you if the parts interchange or if you need to swap out any components to make the newer kit work. Here is the current datasheet for the 3535 - if you have or can find an older version you should be able to tell what parts are different and what you'll need to order. If you can't figure it out, call Sellers Sales in Waco. The guys there know their stuff.

 

[phred113]

After trying the obvious; switching regulators, checking belt, gauge, etc., I guess I'll order the high pressure rebuild kit. The parts look good, but it is quite old, so may as well rebuild while I have it off. It's an 88 model, and they have changed the high pressure configuration on the newer models, so I don't know if I'll have to get the newer type parts or not. Anyone know? Also, is Kleen Rite the best price for this stuff?

I do not understand how you think it could be the seals on a 22 year old pump. The drive end may be on its final legs.

Try an Arimitsu 3615 a good, quiet replacement.

 

[MEP001]

It doesn't sound at all like it could be a problem with the drive end.

Why are you always pushing Arimitsu and knocking Cat?

 

[washtubman]

Why the drive end? There is no knocking, shaking, etc. Ceramic plungers are in good shape also. Also, it is running at the same rpm as before, so that is why I believe its in the head (seals, packings). I really don't believe I need to spend money on a completely new pump. These 3535s are built like tanks.

 

[helpfuljames]

It doesn't sound at all like it could be a problem with the drive end.

Why are you always pushing Arimitsu and knocking Cat?

I think phred113 likes our pumps and tries to put in a good word when he can and sometimes people go overboard in their enthusiasm. Once someone realizes that the emperor has no clothes, they tend to be passionate in alerting others to 'see'. Some get upset at the messenger and others get upset at being deceived. We suffer from former and benefit the latter.

The drive end has many parts that contribute to drag, especially as bearings start to wear, connecting rod journals can become rougher and start to drag, and so can the plunger rod sleeve journals with all those years of wear. I do not think phred113 is too far off base, but you can have your opinion.

Seals tend to wear larger and provide less drag, so the seal theory is much less likely. The high pressure seals could be leaking into the low pressure side and cheating some of the flow, but besides this, I do not see how the seals could to be to blame.

You tend to be the all knowing guru here, and I am just a pump guy, so no doubt there is more to this than I can imagine.