This is all new to me. I have a 1968 ss 12 hydro-trac, model # 143-582032 . If these questions have already been answered and I missed them please point me in the right diredtion, for I did not find the answers. From what I have been able to find out is that the hydro unit is a sundstrand. Can anyone please tell me what model sundstrand or how to identify it? I am also looking for a service manual/parts break down. I have found what looks to be a similar unit [early model wheel horse], but it does not tell the model number.
Does anyone know where a new filter can be found?
The unit will not free wheel. The lever does turn the shaft going into the hydro unit, but still it does not free wheel.
Any advice or pointers would be greatly appreciated.
First off, welcome to the forum! Received your pm questions today and figured I'd answer here.
There was a thread discussing some few available rarified filters that would work but I've also been unable to find that this much later (edit - found it - that thread is linked below down near the end of this post). Maybe some of our fellow forum members kept a link to it? I was unable to find a gasket but the old one came off totally clean. However, it has become very hardened over time so I reinstalled it with minimal oil resistant RTV and no leaks there.
Also in that thread about SS filters and such were some measurements I took of various oil levels and what worked best. That's where all my notes were and I'm a bit annoyed I can't find it. If anyone does find it, that would be much appreciated and I'll keep a pointer for sure this time! I'll keep digging for it and if I find it, I'll post back here with an edit or two.
To this day, my 1968 Sears super hydro 12 trans has never freewheeled. The lever that is there that I thought would make it easy to push around the garage and such but it does not. I've been warned to never run the tractor with that release lever pulled up as it reportedly causes immediate internal damage.
Were I you, I would probably first source a filter. Once that arrives, decide what fluid you're going to use - opinions vary on that. My hydro was kind of noisy on Dex 6 so I went to something else described in the below linked thread near the end of the post. Also, I found the gear oil to be very low so I changed that out as well. Anyhow, while changing the trans oil and if you find nothing disastrous in there, maybe go ahead and put it together, fill it up and bleed out the air/top up the trans fluid a few times with the tractor up on a jack, then I would suggest trying it out to see how it runs. That may not be possible if the engine isn't up and running yet, obviously. If it's not running but you find nothing scary in the trans pan, I suspect the hydro unit will work fine. Just please make sure that bypass lever is never open when running it. Some people bleed some of the hydros with the bypass open and the tractor up on a jack. But I don't; read too many stories of damage tied to having the bypass open when running. Your tractor; your call, of course.
I've been unable to find a manual for this hydro but there is a photo copied manual a guy sells in ebay for Massey Fergusons that have a very similar trans but with a different setup for actuating forward and reverse on top of the trans.
As I found on mine, a common scenario with these is for the top control shaft O-ring to go flat and start leaking. This bathes the entire unit in oil over time so very hard dirt and sludge had totally filled all the fins on my unit. Probably a rite of passage for hydros, but I had to dig all that garbage out. If memory serves, I then cross ref'd the Massey top o-ring and bought several in a material expected to resist trans fluids and such. I learned that 3/32" thickness was right but I don't remember the OD.
Not a lot of useful info in this post. I'll see what else I can dig up and post back.
I believe the unit in my tractor is very similar to a Jacobsen Hydrogear. I think I have a pdf manual for that but I think it came from manuals here in the website.
Hopefully, the below will be a pdf of an overhaul manual. It appeared to me to be most similar although the top control shaft and plate are obviously different.
Hydro Gear Overhaul.pdf 5.52MB
Ok, here is a link to the discussion on possible alternate filters. What I did is working fine, however, I haven't heard from anyone else following that discussion about whether it worked out for them or not. I consider it to be iffy - proceed literally at your own risk on this. If I had it to do again, I would personally probably try the same filter without the hacks I did. Just the normal spring retention and hope it doesn't tip over during installation.
http://gardentractor...= hydro filter
Well, that's about all I was able to dig up. I hope some of it is of use. Also hoping better informed forum members can provide you with some input.
Edited by MountainMichael, September 28, 2015 - 01:07 PM.