Hydraulic control valve leak

R

rdmcclen

New member
I have a '49 Cub with a Controlvalve_small.jpgcontrol valve leak in the touch control unit. I am on my third disassembly and repair of the valve. In reference to the picture, do I have the control valve o-ring in the correct position, am I missing an o-ring? The touch control unit works great but I have a puddle of hydraulic fluid under the tractor every time I use it.
 
Hi,
The Cub service manual shows the o ring goes in the front groove in the control valve, like you have it.
The manual says take the valve out, or put the valve in from the front of the unit, not the head, or rear end.
Below is the page with info.
https://farmallcub.com/rudi_cub/www.cle ... -08-23.jpg

Put plenty of new Hy-Tran or other approved fluid on it when putting it in.
Check the hole at the front of the unit, feel around it to be sure it is smooth. File off any roughness. It can cut the o ring to put it in if the metal is rough there, then it will leak.
They have said on here the o ring is a special size, if you are using one that is too small, it could leak.
Below is a listing for a new one at TM Tractor Parts, it is a Case IH part, it says. :)
http://www.tmtractor.com/new/hy/674fp.htm
 
Thank you, Glen. A follow up question, could fluid be coming from somewhere in front of the o-ring on the control valve? My o-ring is from TM and there are no nicks on it. If you feel the control valve the o-ring sits well above the valve and should provide a seal. Also, is there an adjustment to the control value, for example, could I be extending/retracting the valve to where it no longer seals?
 
Check the two bolt heads above the control rod on the front of the block. If those aren’t tight it can leak there and drip down over the control rod and make it look like the control rod is leaking when it might be fine.
 
That is, IF you have the earlier block. The later block didn't have those two valves located on the front side.
 
Dale Finch":13ekm2al said:
That is, IF you have the earlier block. The later block didn't have those two valves located on the front side.
Click to expand...

That’s true, the later blocks don’t have that. Noticed that in the different how tos. He said it’s a 1949 so it’s likely an earlier block. But who knows someone may have swapped a newer on there at some point.
 
You must log in or register to reply here.
Back
Top