Third Valve for a 544A Wheel Loader

I know this forum is dedicated to ag tractors but I also recall reading past posts of some industrial equipment so please forgive me for posting to this site but I have not found a site for JD Industrial discussions. I want to add the third auxiliary valve (# AT35422) on our 544A Wheel Loader but am having a very hard time finding one. I have contacted over 15 salvage yards so far with no luck including a Google search. My next thought was to see if a boom or bucket valve would work in the third position as the valve bodies look identical and they are a stacked system. However each one has a different part number and of course they are different internally (one has a float position the other not) but functionally they both push oil in either direction. Has anyone done this with success or have any other thoughts? What am I missing here?
Thanks
Brent
 

Brent
Although my knowledge of JD industrial equipment is very limited any ""closed center"" hyd valve should be fine. Part of the differences in valves with different part numbers I think will be the relief valves might have different psi settings but I still think the valves will do what you need. Another difference as you already stated is "float or no float" configuration.
Jim
 
When I worked for Dana we had the hydraulic pump on some 544 loaders. Those loaders have 2 pumps, the regular Deere Piston Pump and an open center pump (the Dana series 20 gear pump) which ran the loader functions. It bolted to the back of the engine flywheel.
 
This is a stacked valve assembly so adding anything other the original will require piping that I was hoping to avoid. I don't have any casting numbers but I'm pretty sure they are Deere manufactured valves. I included a copy of what they look like. You are correct that the loader functions are fed from the other pump which is open center. The closed center piston pump is just for the power steering and I think brakes too.
Brent
a232086.jpg
 

I'm fairly confident JD outsourced those valves and didn't manufacture them.

Adding a control valve is easy on closed center system as all one needs to do is tee into any pressure line and send return oil to return or sump provided added valve is closed center type.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top