Hydraulic pump

[country53]

I've read on this forum about people installing extra hydraulic pumps on JD 420. Where does one mount it and where does one get it? What volume and pressure does a 420 have?

[Stan Disbrow]

Hi,

The only place to mount an auxillary pump on a 420 that I can readily think of is on the PTO shaft. Some of the 440 wheel tractors I've seen used this method for running loaders and backhoes (using the stock pump for power steering). I can't recall ever seeing this done on a crawler, though.

Stan

[Lavoy]

Camshaft driven pump is about 8GPM at 1000PSI, crankshaft pump will do 15GPM, at up to 1500PSI give or take.
Lavoy

[country53]

There is a bolt pattern on the peice that holds the radiator that looks like where I would mount the pump is this correct? Where would I find a pump?

[Lavoy]

If you have the two piece fron casting, then you could install a crankshaft driven pump. You would need the pump, mount, drive shaft, and coupler for the engine. Then you would need a large volume reservoir, and a high flow hydraulic valve.
What is it you are trying to do?
Lavoy

[country53]

I have a 8000# lift capacity mast for a fork truck. I saw a crawler on the web site with a mast on it and decided it would be a good winter time project. I know the fork truck had a 18GPM pump so I wanted to get things sized right. The engine doesn't run enough RPM for the industrial pumps I have access to. I am in planning stages now.

[Lavoy]

An original loader pump will do close to that GPM, but at about 1500PSI, so that may not be enough. It really shouldn't be hard to find a pump that will do 18GPM at 1850PRM and at higher pressure. It would be even better if you could find one that would bolt up to the original mounting plate.
Lavoy