TC Issue

Sun Jan 27, 2013 3:41 pm

Hi guys-
I have a '49 Cub that until today had never shown a hydraulic issue. It has been cold here (-15 was the lowest) and when I went to start the tractor today, the plow will raise but will not stay up. There is no excess oil showing on the dipstick, no leaks that I can see. When I move the lever forward to raise the plow, there is a slight resistance, and when I let go the plow lowers. Over the summer I changed the TC oil. Did I somehow get some water in there that turned to ice and is plugging something up or what? I opened the drain plug and it started to leak out so I know it is not completely frozen. What can I do here? Thanks guys-Josh

Re: TC Issue

Sun Jan 27, 2013 6:57 pm

I bet a small amount of water from condensation has crystalized, holding a valve open or closed, and when the temps go above freezing, your problem will go away.

Re: TC Issue

Sun Jan 27, 2013 7:24 pm

if it has Hy Tran in it the water will be mixed with the oil and should not freeze

Re: TC Issue

Sun Jan 27, 2013 8:05 pm

TSC has a couple of different sized magnetic heaters for engine blocks, crankcase pan, etc., that you can attached to the outside of the TC case to warm up the innards.

Re: TC Issue

Sun Jan 27, 2013 10:29 pm

When you release the lever does it move toward the down position? The friction disk in the lever may be bad.

Re: TC Issue

Mon Jan 28, 2013 6:04 am

Yeah the lever moves back to the down position after I move it to the up position. Would the friction disk failing be related to the cold temps or just one of those coincidences. It does have hytran in it, but i am not positive that I got all of the old stuff out, it was pretty nasty and very very thick.

Re: TC Issue

Mon Jan 28, 2013 8:13 am

Hi another alternative for heating your TC is a blow fan heater blowing hot air and set about 4inches away from your TC 15mins should defrost anything bothering you or a hairdryer can be used also. But you need to sit and watch if case of anything untoward happening :oops:
Donegal Cub :D

Re: TC Issue

Mon Jan 28, 2013 10:09 am

When you're moving the lever, does it feel like it's fighting you? Like, it's pulling away from you?

If it feels normal, but then slips back when you let go, the problem is external, probably the friction disk.

If it's fighting you, the problem is internal, probably a blown o-ring somewhere.

Re: TC Issue

Mon Jan 28, 2013 10:57 am

You don't mention if you checked the TC fluid level and topped it off. Perhaps you didn't have it completely full from when you changed it last summer. It could still work well being down a little until now when it is extremely cold. A simple thing to check.

Re: TC Issue

Mon Jan 28, 2013 11:02 am


Re: TC Issue

Mon Jan 28, 2013 6:55 pm

Thanks guys for all the help so far. The TC is full right up to the fill hole. I also put the tractor in the heated shop for the day and that did not help. I dont think the lever is creeping like the service book describes. It is more of a 'I move it forward, it moves itself right back' kind of deal. If it is a blown o-ring, what should I do next? How do I find it and is there a manual that might walk me through it. Thanks again guys. -Josh

Re: TC Issue

Tue Jan 29, 2013 12:55 pm

Freezing was a long shot. Hydraulic oils, especially hytran, have additives that hold the water in suspension where it can't freeze.

It sure sounds to me like it's a simple matter of the friction disk being wore out.

The TC arms and the control lever are on opposite ends of a little "see-saw" with the valve in the middle. When you move the control lever, it levers on its end of the see-saw and opens the valve. When the valve moves, the arms start moving. As the arms move, they lever on the other end of the see-saw, and closes the valve.

If the control lever moves easier than the valve, the arms will move the control lever until it's all the way in one direction, before it will start moving the valve.

Try holding the lever in position until the arms stop moving. If that works, then it's a friction disk problem.

Re: TC Issue

Wed Jan 30, 2013 12:32 am

I had a problem similar to yours not too long ago. I could raise my belly mower and
it would go back down seemingly under a spring-like pressure. There was a leak also and I had another
TC unit so decided to change it out. When I took the hydraulic lines to the pump off
I found the outlet line to the pump was plugged with a wad of crumpled brass from the
oil strainer that was coming apart. Only a very small amount of fluid could get through
and was causing pressure to build up inside the unit. I went ahead and changed it out.
Planning to rebuild the one I took off but still haven't opened it up to check it.


Re: TC Issue

Wed Jan 30, 2013 6:05 pm

Well I got it figured out. Somehow there was a lot of pressure in the unit. I opened the fill cap just to check the level of the oil to be 100% sure, and the trapped air blew out. I checked the level, put the cap back on and tried it. It worked like normal. Not sure yet what was goin on but problem solved for the short time. Thanks all for the advise and ideas, I actually dont mind having a few problems now and then because each time I do I learn new things. Thanks guys, Josh

Re: TC Issue

Thu Jan 31, 2013 1:43 pm


Glad you found the problem and thanks for letting everyone know what it was. It is an excellent way to finish off a snag. Bleeding the system is usually the best way to solve a lot of extraneous issues, sometimes the system is just full of air :lol: