rebuild of hyd. valve?

[suther51]

New here, thank you for the sight, very much appreciated!javascript:emoticon(':D')
Just bought a '56 420c, there are a few things that it needs done to it. but the first thing I'm looking at is rebuilding the valve that raises the blade. The valve sticks at times when trying to raise the blade. A tug on the handle has so far freed it up. The valve also leaks much more that I would like. Has any one "been there, done that"? I would much appreciate any comments or help.javascript:emoticon('')

[Lavoy]

Sticking might be in the linkage. If it is the factory valve, I have done many of them. Not rocket science, just kind of a pain.
Laovy

[suther51]

Not sure if it is the linkage for sure but the hydraulics wine when the sticking happens. And yes it is a factory valve. Is there a "rebuild kit"?
Thank you for the help and the web site.

[Lavoy]

No kits, all individual parts. Whining can be improper fluid, or maybe linkage out of adjustment, but nothing that a rebuild will cure. Usually the only whine is when the bypass opens, and that means you have to be at the end of ram travel, or one of the piston in the valve is out of time which is a linkage adjustment issue.
Lavoy

[suther51]

Thank you for the info. This is my first time with a dual piston valve. My first thought was that the piston was sticking and the slop in the linkage was causing an out of time condition.? Well will have to check into it more carefully and in-depth. Thanx for the help.

[suther51]

After a quick look it seems to be a problem in the float latch accentuating perhaps a small amount of timing issue. Sill not sure of the origin of the sticking.

[Lavoy]

Look at the pivot bushing and bolt in the lever itself as well. Make sure both piston move at exactly the same time. One goes in, one goes out, and any thing other than at the same time will restrict flow.
Lavoy