3206 up hills

[Wms1145]

So I finally got the nuts off with an impact and they came right off. Both splines look great on hubs and axle. I have paperwork on the rear when it was taken apart , I believe what happened was the previous owner was using the diff lock when the tires were already spinning and damaged the rear. But it was fixed by a cub mechanic . Was also told if the swash plates inside hydro pump have a crack it I'll make it do what it is doing. Any suggestions is appreciated and I want to thank u all for your time and helping me .

[J-Mech]

I really don't think you have a cracked swashplate. I've yet to see one of those that cracked. On any hydro... not just a Cub Cadet. Maybe you meant the valve plate? If so, the HG unit doesn't have those. Not replaceable anyway.

The 3206 has a Hydro Gear hydrostat in it. Not really the best hydro. Not as well made an the Sundstrand/Danfoss unit.

As far as being able to roll the unit while it's sitting still... well.. maybe your bypass valve linkage is out of whack keeping it from seating the valve? Check the linkage. Also, there is an o-ring on that valve that may go bad, letting it bypass when it shouldn't.
There is also the possiblity that the thrust bearings that the pistons ride on are bad... or have come apart completely. That would cause the issues you have.

A drive pressure check would reveal a lot, but there is no port to test that on this unit. You could do a charge pressure check on it... or when it stalls see if the steering still works ok.

Have you checked the splines on the driveshaft?
Did you replace the o-rings on the charge pump when it was removed?
Do you have a service manual on the tractor and the pump? If not, do you need help getting one?

[jsoluna]

The "chatter" noise you describe, coupled with the strange conditions (under load, changes with difflock engaged and in reverse) and the fact that no other hydraulics are affected makes me more concerned that it is an internal trans issue.

Since you've already got the rear out of the tractor, I'd split it open and check it out.

[Wms1145]

I'm positive the bypass valve is working correctly , had it out and the sleeve slides up over the o-ring smoothly . I have the linkage and plate both off for the test to take the plate and linkage out of the equasion . I even put a little bit bigger and stronger spring in to make sure the button was staying out .22 like the manual says. Also deck on or off it makes this noise. I have located another used cast iron rear and bdu-21l-500 hydro unit with charge pump that came out of a 3235. I can get both for a reasonable price. Any difference between the 500 and 501 pumps?

[J-Mech]

I don't mess with the 3K tractors or the HG units enough to know without looking up the information. I suggest you start hunting and see if you can answer your own question. Perhaps someone here may take the time and do the research for you, but at the moment, I do not know the answer.

[Oak]

Can you drain the oil and see if there is any metal in it?

Is everything tight? There was a guy a while back that was having a similar issue and it ended up being one of the brackets that held the assembly to the machine was loose and causing his issue. It was very similar to your issue the more I think about it.

Can you do a pressure test how the manual shows?

I would love to buy that from you to dissect it but I think you're too far.

Keep us posted and we love pics. Good luck!

[Wms1145]

Hydro filter was clean , no metal at all . When I tore it down I didn't find any loose bolts either . It is for sale if you want a project lol . I just got a gt3235 about a month ago and love it . This 3206 has the 22hp command engine and a 50 inch deck with snow plow .

[J-Mech]

Originally Posted by Wms1145

Hydro filter was clean , no metal at all . When I tore it down I didn't find any loose bolts either . It is for sale if you want a project lol . I just got a gt3235 about a month ago and love it . This 3206 has the 22hp command engine and a 50 inch deck with snow plow .

Sounds like a good repower motor......

Put the good engine in a good tractor and maybe you would have something decent. Something made before 1992 is best.

[jsoluna]

Originally Posted by J-Mech

Sounds like a good repower motor......

Put the good engine in a good tractor and maybe you would have something decent. Something made before 1992 is best.

This is opinion, not fact. I have worked on and owned 3000 Series Cubs and they are well built for the most part. Like any piece of machinery they have their issues, but I have abused the crap out of mine and it is a very reliable machine.

The BDU-21 hydro is tough.
The frame is very well built.
The steering and front axle are stout.
They are easily maintained, and easily operated.


The rear ends have their issues but if maintained and operated properly (difflock models) can handle the abuse. I skid trees with mine and will occasionally have to get a running start to get the tree to budge. No issues. For reference, mine is the open diff with aluminum case.

The main thing that bothers me about the 3000 Series are the oring-style hydraulic line seals. I much prefer conventional JIC fittings.

I wouldn't hesitate to fix the 3206.

[J-Mech]

Originally Posted by jsoluna

This is opinion, not fact. I have worked on and owned 3000 Series Cubs and they are well built for the most part. Like any piece of machinery they have their issues, but I have abused the crap out of mine and it is a very reliable machine.

The BDU-21 hydro is tough.
The frame is very well built.
The steering and front axle are stout.
They are easily maintained, and easily operated.


The rear ends have their issues but if maintained and operated properly (difflock models) can handle the abuse. I skid trees with mine and will occasionally have to get a running start to get the tree to budge. No issues. For reference, mine is the open diff with aluminum case.

The main thing that bothers me about the 3000 Series are the oring-style hydraulic line seals. I much prefer conventional JIC fittings.

I wouldn't hesitate to fix the 3206.

If it's so great, then buy it and fix it. I'll not throw any money at them. If you think that HG trans is "tough" you've not seen much. The Sundstrand units far outlast them. It's not an opinion really.... failure rate of the rear on the 3K tractors is about 25 to 1 compared to the older rears. That number may even be generous.