New Holland 2120 dead headed pump

[MrTea]

This is concerning a 2000 New Holland 2120 compact tractor
I purchased the tractor with this problem so I have no back story or history on it. The tractor would not move forward or reverse so after a lot of investigating I found the power steering pump input shaft was sheared off. The transmission pump is piggyback to the steering pump so they both quit working.
This is potentially good news just one more thing... What caused the deadhead and how do I figure it out? It would be really bad to install a new pump only to have it last a few seconds. There were slivers of metal in the steering pump and wear on one side of the bore. I do not know if this indicates that the steering side was the problem side. The input shaft could have sheared from either pump deadheading.

A couple observations:
The manual says the steering should function even without the aid of the pump. The wheel is hard to turn and it tries but it doesn't steer. I imagine it may if I jacked the front tires off the ground. normal?

On the transmission side I wasn't getting power to the forward and reverse solenoids until I repaired a connection and reconnected a ground. This was off where someone else was trying to fix it. They had removed the control module. I don't know if running it with the control module not working could have caused the damage?

My tractor is a little different than the ones in my manuals. There is a pump mounted behind the timing cover that runs the loader etc.(the loader works fine) then in front of the timing cover are two pumps. The first is the steering pump and the second is the HSS transmission pump. They are bolted together with one input shaft.

 

[countrybumpkin]

What makes you think it had a dead head issue, could be that the pump locked up and broke the shaft.

 

[MrTea]

What makes you think it had a dead head issue, could be that the pump locked up and broke the shaft.

That could be but the pump looked nice or I should say no signs of getting hot. There were slivers off the teeth of the pump gears still in the pump where the gears dug into one side on the lower part. My guess was that it dead headed and the odd wear was from extreme pressure. The bushings and everything else seamed to be in very good shape. I can't be sure what happened though.
Here you can see the scoring and a large sliver:

Slivers on gear:

Output shaft:

 

[oldnslo]

Mrtea,
Since you have no history we can only guess but does it look like someone messed with the any of the plumbing exiting the pump? Reason for asking is that the first valve in the pressure line must be the relief valve. This can be in a block on the tractor, possibly in steering unit, or in front loader valve, etc. If some tried rerouting the plumbing they could have blocked the pump flow and then the weakest link breaks.

 

[RickB]

I would put compressed air (rubber tipped blow gun) into both pump pressure lines and make sure the circuits are open to sump before starting a new pump.

 

[MrTea]

Mrtea,
Since you have no history we can only guess but does it look like someone messed with the any of the plumbing exiting the pump? Reason for asking is that the first valve in the pressure line must be the relief valve. This can be in a block on the tractor, possibly in steering unit, or in front loader valve, etc. If some tried rerouting the plumbing they could have blocked the pump flow and then the weakest link breaks.

The plumbing has not been messed with that I can tell. There is a pretty good leak near where one of the lines goes into the steering ram. When I filled the power steering reservoir it leaked back down over the next couple days. Off the first pump there is a supply line and a pressure line that goes to the steering control valve. Off the second pump there is a supply hose and a pressure line that goes to the HSS transmission control valve.
I will double check all the routing of lines to make sure none seam out of place.

 

[MrTea]

I would put compressed air (rubber tipped blow gun) into both pump pressure lines and make sure the circuits are open to sump before starting a new pump.

That's a great idea. Is it safe for both the steering and transmission lines? Would it trigger the relief valves?

 

[RickB]

That's a great idea. Is it safe for both the steering and transmission lines? Would it trigger the relief valves?

Both circuits are open center and should discharge back to tank so long as the steering wheel is at rest and neither transmission solenoid is activated.

 

[MrTea]

Both circuits are open center and should discharge back to tank so long as the steering wheel is at rest and neither transmission solenoid is activated.

That will be an interesting test. I will get it done in the next day or 2.

Thanks

 

[MrTea]

The transmission circuit was clear but on the steering circuit I couldn't see any air getting through. I pulled the return line and nothing came out.