Antique hydraulic system quit - how to diagnose

[J_J]

If the pump is running continuously, you need a valve that will let the pump flow through the valve when in neutral.

You need an open center valve, so that the cyl will lock when you put the valve in neutral.

Set the relief about 100 psi below the pumps max pressure.

 

[wdchyd]

the next time you open that pump up, there is a drilled passageway just under the shaft seal......is the drilled hole going to the suction side or the pressure side of the pump

It should be going to the suction side, not the pressure side

 

[lhfarm]

J J,

The only repair shop is an hour away and they don't really seem interested in non-commercial jobs. Guess they have enough business. The last time I took anything there it was weeks before they even looked at it and then told me it was worn out and they couldn't find a replacement. That was when I did the research and found that the pump was the same as used on the IH-C. So I purchased the current problem pump off of e-bay. Very possible it is worn out too.

But maybe I should try to take the NOS pump there for testing and see what happens. A "new" IH-C pump is in the $500-$600 range and I'm trying to avoid that.

Well it was good news and bad news on the NOS pump. I finally took it into the repair shop and got a huge surprise. The service counter guy looked at the pump and placed his fingers over the ports. He spun the shaft and said he was pretty sure it was worn out. He said he would take a look at it to be sure and if I could wait he would check it now. I left it and did some errands and he called me 15 minutes later with the bad news. There is too much wear between the gears and the body for it to have been NOS as advertised. When I returned to the shop, he took me to the back and showed me the wear marks. No charge for the service, so I told him to have lunch on me. What a difference one guy can make in a repair shop. I won't hesitate going there again.

We purchased the pump off of e-bay several years ago. As my son said, we would have purchased it even if it had be sold as used, since it came with the proper mount. It looks like I can get a new pump for under $500, so that will need to be the next step.

Thanks for all the advice and help.

 

[J_J]

Just to review some things.

What you want is an external pump to attach to the front shaft.

You can adapt just about any pump that meets your flow and pressure ratings.

You should not have to spend that kind of money for a hyd system.

I have a small hyd pump with a 3000 psi rating and a 1/2 in shaft with a pulley on it. It is driven by the fan belt and controls my lift and tilt on my loader. It will lift anything you can put on it.

That pump with the correct cyl should lift just about any attachment.

Select the pump that has the GPM you want. More GPM's = faster speed of operation.

CHIEF

These pumps are inexpensive and should give you good service.

 

[lhfarm]

Those prices sure look better, but we are trying to do an accurate restoration. Like a lot of antique car/truck/tractor restorations, we already have spent more money than we can probably ever get out of it. If we are sure about the pump, then we can move on to the control valve.

Thanks,

 

[lhfarm]

I purchased a new pump and it works great. I was sharing my experience and the words of wisdom I received here on a jeep forum. One of the fellows posted a link to this video and I found it to be a good explanation of why these pump wear out -
https://www.youtube.com/watch?v=3rA1vOyzYzE&feature=youtu.be

Thanks again for all your help.