boovuc 1,090 #1 Posted June 19, 2009 I think I have a bad hydro on my C121A. I'm not surprised by the lack of maintenance it received before I bought it. (Saved it would be a better phrase)! After it heats up, if I'm on a slight slope, it slows down then resumes when flat and goes faster on a downward slope. All without touching the stick. Engine speed stays constant so I'm betting i'm on borrowed time with that rearend. The oil and the filter were changed and even what i took out of it wasn't too bad looking. Question is: How much are we talking ballpark to have it rebuilt. (I don't have the time and or patients to try myself). It's a Sundstrom 90-1172 rear. I can ship it anywhere free so that isn't an expense. For as long as I have had the C-175, I am in love with this little guy's hydro. Hard to go back to mowing with the 8 speed! Thanks, Boo Vuccola Rote, PA Share this post Link to post Share on other sites
Raider12 13 #2 Posted June 23, 2009 You stated you changed the oil and filter! I have read here on these hydro's the poeple who have them are fussy about using a OEM filter and not a off brand. (if I remember correctly). But also are you for sure the oil level is up to the full mark? Share this post Link to post Share on other sites
boovuc 1,090 #3 Posted June 29, 2009 Yea! The oil level is right on full. I read a few articals on my symptoms and I'm pretty much convinced that I need a rebuild. I'm just going to run it until it gets bad enough to deal with. For now, I can deal with it. PS....It was doing the same thing with an OEM filter on it and proper oil level. Share this post Link to post Share on other sites
calibear2003 4 #4 Posted July 15, 2011 I too am experiencing the very same symtoms with my hydro. How much will I be looking at for a rebuild?? Thanks. PS....This is my very first post lol..... Share this post Link to post Share on other sites
SousaKerry 501 #5 Posted July 15, 2011 IIRC rebuilds are about $700 there is a shop in Michigan that does them I don't remember the name but do a search for sunstrand rebuild and you should be able to find them. If it were me I would buy a used tranny or a parts tractor and take the risk much cheaper. Share this post Link to post Share on other sites
can whlvr 993 #6 Posted July 16, 2011 i was able to get my sunstand rebuilt for 350 cash,but anyway my hydro slows down going up hill if i dont adjust the lever and it will go faster down hill,and my hyro is very strong and just like new(now since i had it rebuilt),but it will pull anything up hill if i give it more lever,maybe my adjustment for the motion control is not set up perfectly but im used to it now,the real test is if it wont pull it self up a decent hill when hot Share this post Link to post Share on other sites
boovuc 1,090 #7 Posted July 16, 2011 Ahhh I don't know why this post appeared??? If you look at the date it's from June of 2009. I don't even have that tractor anymore! Looks like someone spoofed my post! BooVuc Mill Hall, PA Share this post Link to post Share on other sites
nylyon-(Admin) 7,302 #8 Posted July 16, 2011 Nah, someone just replied to an old post with an issue similar to what you had experienced. No spoofing going on here. Share this post Link to post Share on other sites
calibear2003 4 #9 Posted July 16, 2011 can whlvr, can you please tell me where you had your hydro unit rebuilt? Yes, my machine will only travel uphill at darn near a snails pace. However, if I attach it to a fixed object like the the back of my truck, both wheels drive normally. I now feel that I paid way too much for my 312-H. Oh, in regards to who opened up a thread that is 2 years old. That WHO was my lol, I was hoping to obtain some knowledge from all the wise horse owners here on this site. There is so much valuable information here from both young and old. Even more so, from owners all over the world. As far as "Spoofing", there is no trickery and or attempting going on here with me. I am just trying to fix my wounded pony. I purchased my 312-H 18 months ago through Ebay. The seller has 100% feedback and happened to live locally. I was working out of town at the time and he gladly delivered the unit and placed it in my garage. The machine is in beautiful condition, but it also has 1281 hours on the clock. I have not used the machine until this spring, so I did not really know about the operation or issue's of the machine. It's my first Wheelhorse too. Share this post Link to post Share on other sites
can whlvr 993 #10 Posted July 17, 2011 calibear i had my tranny done at a hyrdostatic repair shop,i paid cash and he said it should have been more,these guys do large equipment like huge escavators,backhoes,skidsteers,dozers etc.it was in brampton ontario,i dont know where you are from but if its not near toronto ontario i dont think you will be getting her fixed there,but try these type of shops,i took the pump only to him and the sundstrand manual with it so they could see how it goes together which he found very useful Share this post Link to post Share on other sites
sorekiwi 761 #11 Posted July 17, 2011 Calibear - Before you get too worried about this thing, check that the linkage controlling the hydro is getting full travel and is adjusted correctly. It is reasonably common for a build up of grass etc to limit the travel of the linkage. Also note that some of the posters in this thread are talking about the older Sundstrand transmissions, where as your 312 has an Eaton transmission, I think the 312-H had the heavier duty Eaton 1100, does it have a filter? Assuming it does have a filter the next step (after checking for full movement of the linkage) is to change the transmission oil and filter. Do you have a hydro temp warning light coming on? Other things to check is that the cooling fins on the pump are clean and clear of debri's, and that the cooling fan is present and has all its blades. Share this post Link to post Share on other sites
