1953 JD 40 Touch-O-Matic 3-point Lift arm (Single)

[pcraven123]

1953 JD 40 Touch-O-Matic 3-point Lift arm (Single)
I am not a tractor guy, but Father-in-Law left the tractor to his grandson, so I am trying to get the lift arms working.

Quick history the rock shaft housing was broken so I replaced it in hopes that that was to only issue (would not hold Oil, no oil no lift my thoughts).
After replacing lift still would not work. I removed the rock shaft housing and cleaned the bypass valves, pull rob, check valve, and relief valve. and lift started working but when weight was applied by hand it would just jump up and down, but still would not pick up a implement at all.
After tearing back down I noticed the piston bore had large scratches, so order a new housing. Piston had a bur in the top edge so I cleaned it up removing the small bur. Put everything back together but lift still when weight was applied by hand it would just jump up and down, but still would not pick up an implement at all.
I am at a lost now and don't know what else to do. Any advice would be appreciated......

 

[wore out]

Have you checked the pump for pressure
and flow?

 

[Gene Davis (Ga)]

You need to get a service manual. It will tell you where to install the pipe thread plugs to isolate and check the check valves and the lift cylinder and piston. That is how we did it at the Deere dealership when the 40's were new.

 

[VicS]

If it was run with no oil in the system. I imagine the pump is shot. Sometimes they prime hard. I have had to put grease on pump gear to get to prime.