Ford 4500 hydraulic pump replacement.

[Dana Kent]

I need some guidance here, parts, possible troubleshooting. Hydraulic pump shaf snapped at pump casing, I believe there was a U-joint failure and this caused the shift to snap. That said, is it possible there was a blockage that could have caused the pump to fail like that? Any help would be greatly appreciated. Also having problems finding the correct manual for this equipment 68' Ford 4500 loader/backhoe.

 

[TractorTech]

Welcome to TBN. If the u-joint failed, it is likely the driveshaft got off center and this caused the shaft on the pump to snap.
The 4500 is part of the Ford 4000 - 3 cylinder parts book: New Holland 4000 - SERIES - 3 CYL TRACTOR(01/65 - 12/74) Parts

Pump diagram - 10B03 section
Hydraulic system diagram - 5K01 section

You should be able to find the gear pump aftermarket by typing in the part number on Google or go to Broken Tractor. P/N: D1NN600B pump
Alexander Tractor shows the shaft P/N: C5NNA932C and pump.

Also a good time to look at and at least grease the steering mechanism. Diagram 3E05

 

[Dana Kent]

Wow thank you, that was my first thought but I didn't want to replace it if it was just going to happen immediately afterwards.

 

[ROUSTABOUT]

Check that your by pass is not stuck.

 

[TractorTech]

Also, the hydraulic pump is a gear type, which hopefully you have. If it is the vane pump, there is a lot of plumbing that won't fit the gear pump.
The bypass Roustabout is referring to is in the loader valve, section 05K02, item 1A

 

[TractorTech]

One other thing I was thinking about was that this is an open center system, so if the pump deadheaded somehow by activating a circuit and extending the cylinder to its max, that is when the relief would kick in, so I don't think the relief would be the culprit anyway.

 

[Dana Kent]

Also, the hydraulic pump is a gear type, which hopefully you have. If it is the vane pump, there is a lot of plumbing that won't fit the gear pump.
The bypass Roustabout is referring to is in the loader valve, section 05K02, item 1A

Thank you, I plan to replace like for like, hopefully that's possible, I'm still sourcing parts, pretty expensive and haven't found (not that I want to use one) a used pump. The radiator replacement wasn't a problem. This piece of equipment sat in a barn for 7 years, a few hours looking at systems and figuring out what was what, I got to work on putting some things together, new battery, fuel filters, drained the tank, checked the oil etc. No manual so I had to rely on my basic knowledge of a diesel engine. The tractor was 60 miles away so I couldn't just play with it whenever. I went back the following week, checked the air filter, replaced the fuel filters and started playing with it. With in an hour I had it running again, I moved the hydraulics, then backed it out of the barn for the first time in 7 years. I ran it on the property cleaning up years of neglect. Finally the owners gave me the backhoe/loader, cost me $200 to have it and all 6 of its buckets home. Long story I know but it's important, the backhoe/loader belonged to a guy I met in 7th grade and we remained good friends until his death 7 years earlier, I was asked to manage his estate until it could be sold. I did and still take care of it. The backhoe was his baby and he told his siblings not to let the equipment go cheap. Lol they did but I wanted a better price for the backhoe, guess I got it. Lol thanks for you help it is appreciated
Dana

 

[Dana Kent]

One other thing I was thinking about was that this is an open center system, so if the pump deadheaded somehow by activating a circuit and extending the cylinder to its max, that is when the relief would kick in, so I don't think the relief would be the culprit anyway.

Thats valuable information, basically you're saying the pump can't fail from a blockage the pressure would release, is this correct? This would mean I can put in a new pump and not worry that it failing again because of a blockage or something like that.
Thank you
Dana

 

[Dana Kent]

I have a manual but I don't think it is the correct book for my equipment I will look again and attach the book reference I have.

 

[Dana Kent]

Check that your by pass is not stuck.

Something to figure out how to do.
Thank you
Dana

 

[TractorTech]

Thats valuable information, basically you're saying the pump can't fail from a blockage the pressure would release, is this correct? This would mean I can put in a new pump and not worry that it failing again because of a blockage or something like that.
Thank you
Dana

Not likely. If the drive shaft wiped out the bottom of the radiator, I suspect the driveshaft broke the pump shaft. If you weren't using the hydraulics excessively and it sounds like you weren't, then the oil is going to circulate in the system until you move a lever and bottom out a cylinder.

If you have a picture of the driveshaft, I might have pieces to salvage two for one with new cross kits.

 

[ROUSTABOUT]

Something to figure out how to do.
Thank you
Dana

Just trying to help out.

 

[TractorTech]

Just trying to help out.

Something to think about for sure