3600A No reverse

[Saintbacon]

Hey folks. Thanks for all your advice and suggestions so far.

I'm trying to tackle the next problem on this backhoe loader. No reverse. .
This is a hydrostatic transmission with 2 pedals - one for forward and one for reverse.

Pushing on either pedal seems to work the linkage properly which attempts to twist the control rod (clockwise for forward, counter-clockwise for reverse).

Going forward seems to twist just fine, but reverse only moves like a millimeter from center and just STOPS right there. I tried to grab it with a chain wrench and a vice grip to twist it, but to no avail.
It stops and won't go any further.


Initial thoughts are that there's a piece of something stuck in the transmission that's stopping the shaft from spinning to the reverse position. I have the parts manual and am more than happy to send any
pages that might be useful! Any tips thoughts or advice would be appreciated.

Thanks

 

[Saintbacon]

Bit of an update. I opened up the bottom of the hydro transmission. Doesn't look like there's any foreign material in there, and honestly it looks gorgeous inside. I was halfway expecting a crusty old pile of junk.

So there are 2 pistons in there that seem to control one of two swash plates. I understand that these plates will adjust some push rods which will move the machine.
Only problem is that one of the pistons doesn't seem to be moving at all. Going to do some further testing, but figured I'd post in hopes that somebody might have some experience with this kind of set up.

Thanks in advance if there's any advice!

 

[BarnyardEngineering]

It might be worth your time to give Herr's Hydraulics a call. They have established themselves as the go-to for hydro repair on farm tractors. Maybe they can offer some suggestions.

You've got a double-whammy here. The 3600A is an industrial model, not a farm tractor. Once you get past the engine, the similarities to farm tractors end. IH dumped the construction/industrial division in the early 1980s, and the company that bought them, Dresser, was only interested in the bulldozers. They dropped support on everything else right away so your tractor has been an orphan for a while now.

 

[AlinMO]

Like Barnyard said Herr's seem to be the knowledgeable people on hydrostatics. Here is there web site https://herrshydro.com/