hydraulic question

[muleboss]

Can the seal on ( under the leather boot, the piston control rod) the front of a hydraulic unit be changed without taking the unit apart? If so do you have to get a whole repair kit or can I just get a new seal? Thanks Bob

I think that is called the control valve seal ring

[Dale Finch]

The control rod o-ring can be replaced without disassembling the touch control block (it pulls out toward the front), and TM Tractors has the o-ring:
http://www.tmtractor.com/new/hy/674fp.htm

I needed to do this one time and was told you could do it with the block in place. I tried that, but by the time you disconnect the hydraulic lines, unbolt the block, and try to lift it up high enough to pull out the control rod, it's not worth the hassle. I wrestled it for a while, and finally pulled the block, set it on my work bench, replaced the o-ring, and put it back in. Would have saved a LOT of time and effort if I had just done that in the first place!

[muleboss]

Dale thanks for reply. Will take it off and try it.

[Dale Finch]

Just to let you know, that is a fairly small but thick o-ring, and it is a bitch to get on. Make sure the forward end of the control rod has NO burrs on it, because you will be working hard to get the o-ring over the end, and you don't want to put any nicks in it!! Use plenty of HyTran (or equivalent) for lubrication.

[muleboss]

Do you know the size? Maybe I can get it local hardware or auto store.

[Dale Finch]

I believe folks have tried before unsuccessfully. I did measure one from TM Tractors' kit last rebuild, but no guarantees it is correct!
IH Part #350 672 R1. 15/32 x 25/32 x 5/32"

[muleboss]

Might be a silly question. Will the check valve actuator pull all the way out without something falling inside? I am replacing the o ring. Thanks Bob

[Dale Finch]

Do you mean the CONTROL valve? If so, yes, you can pull it out without any disasters!

[Glen]

Hi,
Below is the listing at TM Tractor for a new Control Valve o ring. It has a pic on the page of where it goes.
The valve just slides out of the Touch Control.

http://www.tmtractor.com/new/hy/674fp.htm

People have said on here that they couldn't find the right size o ring at other places.
It is a Case IH part in the listing, it says.

When you remove the valve, feel around the opening in the block where the valve goes in, and be sure it is smooth. Smooth it if it is rough, any roughness can cut the new o ring.
Use plenty of Hy-Tran fluid, or other brand approved fluid when putting the o ring on the valve, and when putting the valve in the block.

Dale, you put the link to the pump shaft o ring in your post above.
muleboss, the pump shaft o ring doesn't work on the Control Valve.

[Dale Finch]

OOPS! Using my phone makes those thumbnails way too small! Sorry about that! I'll go change it now...thanks, Glen!

[muleboss]

Thanks, Checked shipping from TM, $11.50 seems a little high for shipping.

[Dale Finch]

Call Ron, and see what he can do about the shipping costs. He might do an "actual cost" deal. Worth a call.

[cavingreer]

I found a cool way to get that piston back in. Get a 24" squeeze clamp. Get the piston in place and clamp the end of it and the end of the block and you can squeeze it gently into the new O ring without damaging it