Iíve had a 1969 400 with the 7400 loader for a couple years and recently pulled the loader valve apart to reseal it and the pressure relief valve on the inlet port came came out in pieces. The brass insert in the spool was unthreaded and sitting sideways.
It seemed apparent how it should go back together, I got my thread file out and cleaned up the brass insert so it would thread all the way down, inserted the orfice and spring (there was no shim at the bottom of the port) and put it back on the machine.
The loader operates extremely slow however it has full lifting capacity so it seems like the pressure relief is assembled wrong but I donít see another way to assemble it. Does anyone have any info on these old valves? The JD parts manual seems to agree with my assembly but itís not a very good drawing.
The backhoe works normally so I know the pump is fine.