1250 Cub Cadet help!!!
 

Hi everyone,

I recently inherited a 1250 IH cubcadet hydrostatic (75' I think.) it's in ridiculously good shape and obviously well maintained. It sat a my uncles house for 3 years before I was able to pry it away from him. It started right away and purrs like a kitten. The problem- it won't drive. Let me elaborate; it will creep forward a few feet then stop. No reverse. It is 'trying' to move. Checked the hydro fluid; full and pretty clean. I would love to get this gem up and running as it is nearly 15 years older than myself! Is there a tran bypass I'm not seeing? Should I replace hydro filter? It rolled relatively easy when we pushed it a short distance to the trailer. It also rolls when the engine is running. Again it sat for nearly 3 years (or more)

Thanks a bunch!

Your hydro valves sound like they are bad. I would change them or get them fixed. A hydro fluid and filter change would help also. I know that there is a guy that makes them or something like that on here. Hopefully some one else can help you with that hook up.

First, welcome to OCC.........:Welcome2:

The first thing I would check, is to see if there is a broken "spirol pin" at the Hydro Transmission Input Shaft to Drive Shaft Coupler. See image. These are known to break. What is typically seen, is the drive shaft spins normally but the input shaft to the hydro unit either spins slowly due to friction or not at all.

the spirol pin looks to be in good shape (shaft is turning pump)

filter?

oh, and here's a few pics of the beauty

Make sure it keeps turning when you try to move it. You have to look at the pump shaft. If the key is sheared, the driveshaft will always turn.

You weren't kidding, that thing looks great.

The filter can be seen from the bottom side, coming from the hydro pump, with the top facing the front of the tractor. Hard to miss, unless it's covered in dirt/oil sludge. It looks just like an automotive oil filter but it's not. It's a hydro specific filter and can be found at places like NAPA.

Google your Cub model for the hydro filter number, or someone will be along shortly with the number fresh off the top of their head!

:beerchug:

Napa: 1410
Wix: 51410

:biggrin2:

That is one nice looking Cub for sure. I would lean toward the spirol pin too, but I am far from an expert.

Your situation will most likely be, the Spirol Pin failure or a plugged Hydro Filter. Either will cause a lack of fluid to travel throughout the Sundstrand Hydraulic Unit.

If its not a broken pin I'd go ahead and change the fluid/filter, seems like when they sit the fluid gels in the filter which causes all sorts of issues.

ok so here's an update; changed the fluid and the filter.... nothing. spirol pin(s) are intact and the pump has power. pulled the plate off the differential, looks good. pulled the valves (at least i think they are valves) off the top of the pump as i hear these can get gunked up but they are spotless.

still no power to rear diff.

what's next?

Go to this link. Down load the Service Manual. Look at page 2-93 and perform the Charge Pump Pressure test. Tell us what you find..... Service Manual

- pressure test yielded about 95 psi @ idle

Even at 95 PSI it should work. More than likely the charge relief valves (the big ones that you are holding in the pics) are stuck. Could be a charge pump issue, but more likely the valves.

Did you try moving the lever with the gauge installed? If so, what did it read then?

The pressure would drop to about 70 psi or so with the lever engaged and would be 'jumping'

I'm starting to think this is a charge relief valve problem... Are the ball bearings in the valve supposed to be freed up? They were rock solid. How can I diagnose a bad valve problem?

YES, there is to be "free travel" of that steel ball inside the valve.

There is your problem. You have three choices:

(A) Soak the valve(s) in a solution (ie: PB Blaster) and get the steel ball to travel freely.
(B) Send the valves into someone for rebuild.
(C) Buy new valves.

Try soaking in kerosene, or some brake fluid should do it.

Brake fluid? Explain that one.... :bigthink:

Yup I think we're on to something... I will play around with it this afternoon and update after. Fingers crossed! I don't want to buy new ones that's for sure

Good news everyone!!

Soaked those suckers in some PB blaster and gave them a few taps in the floor- good as new. Installed them and the thing runs great. Thanks to everyone who helped me out on this one. Glad to give this buggy a second chance. Great first experience on the forum!

Ill post some pics tomorrow

It looks like a great cub that was very well maintained. Even so, those valves can stick if the cub sit for a while. Lots of great advice here and great fellas. I'm glad you got a nice cub and deep down, I bet your uncle is, too.

Cub Cadet 123

Something an old farmer told me to do with a stuck valve on a model T. Worked like a charm!! ATF usually works too. But i had a solenoid in a auto trans for OD stickin and i put bout a cap full of brake fluid in that and after drivin a little while it started shifting much smoother. Why it works? Not sure just know it seems to. Unless i have had one hell of a chain of coincidence over the years!!

Congrats! Love to see old machines working again!

Brake fluid makes rubber seals and gaskets expand so more than likely your clutch pack sealing rings on the trans were affected by this or possibly the o rings on your solenoid valve if the bore was worn or something, both of which are a very temporary fix. I have never heard of mixing brake fluid to clean out things like valves but ATF in the oil for a bit yes. I'm going to look more into this, interesting to say the least