Bar Nuthin 460 #1 Posted December 6 What is the difference between the three model numbers of the piston-piston Sundstrand hydros? My C-120 has a 90-1136. I have a lead on useable 90-1140. I would like to keep the tractor in service while I overhaul one (or the other). Are they interchangeable with my current transaxle? If there is a difference in models, which one would be considered better to overhaul (assuming they are in similar condition) Share this post Link to post Share on other sites
953 nut 55,734 #2 Posted December 6 Both of them were used on the 1976 C series tractors so there shouldn't be a problem. Perhaps one had the set-up for a hydraulic lift and the other didn't, or could be the pulley shaft isn't the same or something like that. Take a look at the manuals section, The 12 HP models 61-12KSO1, 61-12KSDO2, 61-112KSO3 AND 61-12KSO4 ALL HAD THE 1136 AND THE 16 HP units of the same number sequence had the 1140. I seem to recall a thread not too long ago about the input shaft on the 16 HP Sundstrand being splined rather than keyed. Perhaps @ebinmaine or @daveoman1966 can give some more information on this. 1 1 Share this post Link to post Share on other sites
Bar Nuthin 460 #3 Posted December 6 (edited) @953 nut Thanks. I've been studying a parts list from another thread, trying to detect any differences. All three models use the same parts list, so I feel like I'm missing something. I'm not sure who compiled the parts list, but they seem to have done a thorough job. SUNDSTRAND PUMP & MOTOR Parts list (1).pdf Edited December 6 by Bar Nuthin Share this post Link to post Share on other sites
pfrederi 17,856 #4 Posted December 6 The key vs splined is probably the only significant difference. 2 Share this post Link to post Share on other sites
gt14rider 795 #5 Posted December 6 Daveoman posted this in one of my post.ill look for more information. 1 1 Share this post Link to post Share on other sites
953 nut 55,734 #6 Posted December 6 57 minutes ago, pfrederi said: The key vs splined is probably the only significant difference. If you get the pulley with the Sundstrand you buy then all is good. 1 Share this post Link to post Share on other sites
gt14rider 795 #7 Posted December 6 My post was. (90-1136 teardown question), has some other information, hope it helps. 1 Share this post Link to post Share on other sites
Bar Nuthin 460 #8 Posted December 6 53 minutes ago, gt14rider said: My post was. (90-1136 teardown question), has some other information, hope it helps. Excellent reading! Thank you! Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,090 #9 Posted December 6 All the 16hp C-series used the 90-1140 hydro and the hydraulic lift shows as being standard equipment on all. The smaller hp hydros used the 90-1136 and the hydraulic lift shows as being optional. 2 Share this post Link to post Share on other sites
Bar Nuthin 460 #10 Posted December 6 50 minutes ago, gwest_ca said: All the 16hp C-series used the 90-1140 hydro and the hydraulic lift shows as being standard equipment on all. The smaller hp hydros used the 90-1136 and the hydraulic lift shows as being optional. So, I'm guessing I would need to confirm that the charge valve and implement valves are in the correct ports for manual lift. (Unless someone has a good deal on the parts needed to convert to hydro-lift ) Share this post Link to post Share on other sites
gt14rider 795 #11 Posted December 6 This was what I found 2yrs ago. 2 Share this post Link to post Share on other sites
ebinmaine 68,205 #12 Posted December 6 14 minutes ago, Bar Nuthin said: So, I'm guessing I would need to confirm that the charge valve and implement valves are in the correct ports for manual lift. (Unless someone has a good deal on the parts needed to convert to hydro-lift ) You MIGHT be able to swap parts from one to the other for manual vs hydro lift. 2 Share this post Link to post Share on other sites
ebinmaine 68,205 #14 Posted December 6 @gt14rider Me n you may have a chat in the next few weeks so I can clearly see what those pics mean. I have a 1978/79 C121 with manual lift I'll be making into a hydro lift. I should have all the required parts here in/on a 78 C141 1 Share this post Link to post Share on other sites
gt14rider 795 #15 Posted December 6 (edited) Not a 100% on this I plan on switching one on my 73nn. If you don't have a lift you should have cone,spring,maybe a shim pack, o ring and cap (right side) and nothing on left.(see pics) to get the lift. Take spring #55 on right and move to the left add (ball #48). Add new spring #49 to right side. Am I making any sense. If there is anyone out there who knows please chime in. Edited December 6 by gt14rider 1 Share this post Link to post Share on other sites
gt14rider 795 #16 Posted December 6 I've been playing around with a parts list for the piston to piston sundstrand. I'm not a good typist and I have a attention span of a nat,so still a work in progress. Trying to get good part#s and were to purchase still have a lot to do but what do you think of a complete overhaul kit. 3 Share this post Link to post Share on other sites
ebinmaine 68,205 #17 Posted December 6 54 minutes ago, gt14rider said: but what do you think of a complete overhaul kit. Excellent idea! 1 Share this post Link to post Share on other sites
pfrederi 17,856 #18 Posted December 7 Check out the pinned post on Sunstrand O rings top of this section 2 Share this post Link to post Share on other sites