450 Hydraulic Flow Control Valve

[RyanKve]

Good evening all.

I have a Farmall 450 diesel that you all probably remember. For a while it has had the issue with intermittent hydraulics. I am lead to beleive that it is the flow control valve, springloaded on the side underneath the plug with a snap ring. I believe this because while playing with inserting it back in, sometimes it will get stuck if not at the exact right angle. If I take this out, really lube it up, put it all back together, and start the tractor again, it has a chance of working. I originally looked at the screen when the issue first arose and it seemed to look fine. I haven't looked at it since and have much more knowledge about it now, but it is still the same symptoms. Playing with the valves to build pressure does give powersteering or hydraulics at all. Occasionally after a while on rides down the road I'll all of a sudden, without playing with anything, have hydraulics again. Is there a way that I can remove this system (It should be a ps priority if I remember correctly) and still have all hydraulics? Or is there an easy fix or possibly something I am overlooking. Thanks, Ryan.

 

[Janicholson]

If you pull the sticking valve, look it over to see if you can see any bright High spots. if so use 1200 grit silicon grit paper to buff it down and dry it again. don't get carried away. and clean it dry before putting it together. Jim

 

[RyanKve]

Originally I took it out and sanded down some of the edges with 2000 grit sandpaper and some oil in case of burs, I guess. Made sense at the time. When I put it back together, the hydraulics worked consistently for a few weeks, then went back to intermittent. When I get to pulling it out again, I'll double check for high spots.

 

[RandyM]

Im not sure if this will help, but I had issues with my F450 fast hitch not working or working itermittently. I replaced the hydraulic pump, then the safety/priority valve, and then the fast hitch control valve. Done separately to see which may be the problem. The changes did nothing to resolve the problem. My problem was fixed by a putting new o-ring, spring and ball in the check valve mounted under the seat. Most of that original o-ring was gone.

 

[RyanKve]

Thank you. Ill try this too when I get my next chance.