1975 Cub - Hydraulics Not Working, Control Lever Stuck

[AL Farmall Boy]

Guys.....I'm sure you remember me posting off and on about the 1975 Cub I am restoring as a back burner project among my other projects. I am just now getting everything back together. We just started it for the first time since this past December when I had parked it at the back of the shop to prepare for paint. I have put the tractor back together (everything but the hood, sediment bowl, decals, headlights, and new fuel line. We wanted to try and start it to make sure all systems checked out ok before putting the hood back on. I got some fresh fuel to the carb, and turned the key and it started right up with no choke and ran perfect just like I had parked it there an hour before.

THe only issue I noticed is that before I started the tractor, The hydraulic control lever was about 3/4 of the way forward (towards radiator), and once it started it moved back on its own to the most rearward position. We have tried working the lever by hand while running and it seems to be stuck....really stuck. I took the TC fill plug off and alot of air escaped (engine not running). We started the tractor back up while plug was out and it still will not move. Can't see anything binding it or anything bent. What could it be? COuld it be something inside stuck or binding (valve or something ), or could it be the paint on the exterior of the unit somewhere? We have painted many, many Cubs in the past and have never had or seen this happen. Surely it is something simple, as I wouldn't want to rebuild a previously perfectly working TC unit.

THANKS and HOPE YOU"RE ALL HAVING A GREAT MEMORIAL DAY!

[tmays]

Check to be sure the end of the control rod is not outside the stops where it connects to the hydraulic body

[AL Farmall Boy]

Nothing was removed as far as the hydraulic system goes so I'm sure the rod is still where it was before I parked the tractor.

[AL Farmall Boy]

Here are some pics if they are of any help

[AL Farmall Boy]

I would like to correct my previous post and say that the control lever didn't go all the way back when it moved on its own. It went to where you see it. I'm sorry for incorrectly stating that. I was typing that post on memory.

[tst]

The rod looks like it rubbing/stuck in the picture, you can see where the paint rubbed off on the rod
Tim

[AL Farmall Boy]

It's just barely touching Tim. Doesn't seem to be causing the problem. I'll remove the linkage to make sure though. If I push or pull on the lever any harder it's gonna bend or brake the rod. I'm about to go look for the "stops" tmays was talking about. I've never had to mess with those on a tc unit so I'm gonna goose if I can find those and see if they are ok

[John *.?-!.* cub owner]

Did the rockshaft ever move during any of this? Check the linkage that connects the control lever to the lift piston etc. and make sure it is not bent or binding. maybe bound with paint.

[AL Farmall Boy]

John got it! I had a feeling it had to do with paint but it was stuck so hard I thought it was simply bound up by something solid....and also because I stuffed a rag over the cylinder and linkage so when I was painting it would keep it covered. I'm guessing some got in there because I sprayed the cylinder and linkage underneath liberally with PB blaster. Took a small pry bar and gently bumped the arm that the hand control linkage connects to. It would come loose and move all the way in the other direction and lock down. It took me about 10 cycles back and forth with the pry bar until it freed up and now it works effortlessly and it will stop in any position I want it at. Nothing turned out to be bent or broken. It works Just like it should.

This is something for folks to remember when painting, even though I thought I covered the area, I'm thinking some got in there from underneath when I was painting the underside of everything.

I'll be sure and post some pictures once it is all buttoned up. I'm really proud of this tractor,
And the way it turned out!

[John *.?-!.* cub owner]

I wish I were smart enough to claim I knew that, but go here
http://www.cleancomputes.com/Cub/Blue%2 ... ontrol.htm
and scroll down to the trouble shooting steps, step 8, and #3 under that.

My electronics instructor in college told me that a good technician did not know everything, but he knew where to find it.

[Matt Kirsch]

You can see the front stop in the first picture.

Something is applying pressure to the control spool and pushing it out. That is why the lever went back. I'm thinking the TC unit has to come off and come apart for a good cleaning and rebuild.

[CharlieK]

thanks for that info, john--hope to see ya at the bash

[John *.?-!.* cub owner]

Unfortunately due to my back, trips that long are not an option. About the only thing I will get to this year will be Cubarama.

[AL Farmall Boy]

You can see the front stop in the first picture.

Something is applying pressure to the control spool and pushing it out. That is why the lever went back. I'm thinking the TC unit has to come off and come apart for a good cleaning and rebuild.

It works perfectly now. I think there was just a bit of paint causing it to stick. I can't imagine what else. It works effortlessly with no hesitations or leaks. It stops where you want it in small increments. Couldn't ask for a better working TC unit.

Thanks for the help guys. I'll have to post a picture and video of it soon!

[redman36]

using cub today front blade was working ,then I raised it and would not go down . went to full up and then back down on control with no response. Noticed some smoke from breather ,drove to house and shut off. I then checked engine oil and found to be 1 inch over full. Checked hydraulic oil and cant touch with little extended in hole. suspect seal blown on hyd. pump. any ideas before I start is greatly appreciated. Grey Wolf