Weekend Freedom Machines banner

1 - 1 of 1 Posts

5,157 Posts
Discussion Starter · #1 ·
I plan on converting my 1983 JD 318 from H2 to H3 hydraulic system. The valve to be installed I believe came out of a Deere 430. Before being installed I would like to inspect the valve and replace any parts that could be a problem later. I know a typical problem is the detent spool is difficult to engage due to contamination in the cap not allowing the detent balls to move freely. This needs to be cleaned to insure smooth operation.

I just scrapped a 317 which had a control valve that the spools would not move so I tore this valve apart to learn what is involved in the restoring a hydraulic valve. I was surprised with the ease to breakdown the valve. I did not see the need to breakdown the spool components.

Removing the valve:
  • Drain hydraulic fluid.
  • Disconnect the linkage between levers and control valve.
  • Disconnect hydraulic adapters to remove tubing from the valve. Also need to disconnect inlet and outlet plumbing.
  • Remove two nuts on adapter side of valve.
  • Remove the valve.
Tools needed to disassemble the valve:
  • Pick
  • 3/8" allen wrench
  • 11/16" combination wrench
  • straight screwdriver
  • ball peen hammer
Steps to disassemble:
  • Important issue: parts need to be reassembled in the ports they were removed from. They were paired with those ports during assembly to minimize fit of parts and reduce leakage between parts in the bore.
  • Use the pick to remove the plugs from the end of the caps.
  • Engage allen wrench in opening covered with the plug and remove the caps.
  • When removing the cap with the detent balls be sure to cover the cap area with your hand to capture the the detent balls and springs. I you do not do this I can guarantee you will be buying detent parts. I heard them bounce off the garage door but have been lost forever.
  • The spools can then be slid out of the bores.
  • Remove the adapters from the work ports to replace o-rings. I found these o-rings were brittle and has taken a triangular set.
  • Remove check valve plug and replace oring and springs in those 3 ports.
Thats all there is to it. Really quite simple.

During reassembly you will need vaseline/white grease to lubricate o-rings and small container of hydraulic oil to lubricate parts.

I apologize that some of the photos are kind of fuzzy. Photos of spool ends are intended to show the chrome has peeled under the o-ring area of operation. This is the reason spools did not operated. Condition of the spools will damage o-rings and cause leakage. This valve will be scrapped.


1 - 1 of 1 Posts