ford 420 backhoe

[markmc60]

I have a ford 420 backhoe, it is so weak it will not pick up a round hay bale, pitiful.
I want to replace the Hydraulic pump but the previous owner swapped it with a smaller unit I think and i do not have the make/model/GPM of the original pump. How can I find that information to get a replacement pump?

 

[J_J]

What do you mean by weak? Have your did a pressure check. Do you know if the cyls are good.

Does the BH have it's own pump?

I would install a hyd pressure gage in the hyd system before the first valve and use it to monitor and trouble shoot the hyd system.

 

[markmc60]

what I mean by weak is it is weak, will not lift a roll of hay, wont lift the back end up on the stabs....weak
all the cyln bad?...no,.... the cyln do not leak, it does not have the power the pump should be putting out, the previous owner paid a beer lover to replace the hyd pump, he did, pretty sure he got an old worn out pump for it and I am not sure what the original pump is suppossed to be.

and yes, it is the pump mounted under the front cowling, runs off the crank.

all I am looking for is the original part number and GPM, since I do not have a parts manual.

 

[J_J]

The point I am trying to make here is that it doesn't matter the size of the pump, the pump pressure are about the same 2500 to 3000 psi. If the pump is not meeting those specs, then it could be considered weak. Force produced by a cyl, is based on the pressure, bore and rod size. So, if the cyl are good, and the pump pressure is good, then the loader or 3pt is doing all it can. In order to boost things beyond specs is is necessary to increase the pressure or get larger cyl.

GPM's determines the speed of cyl movement, or hyd motor speed.