champ97 0 #1 Posted July 16, 2013 Hi have a 520 h with the hydra/unidrive trans,has run great until today,mowing grass on flat ground rear tires locked up,tryed reverse moved about 2 or 3 feet locked up,tryed forward same thing.. Jacked rear up everything works normal, turn wheel one way other tire moves opposite direction. Start moter while rear is off ground,try to go forward or reverse makes a couple revelutions and seems to hydralicaly bind up. Have no experiance with this type of trans..any ideas..thanks Share this post Link to post Share on other sites
hummod 0 #2 Posted July 17, 2013 Champ97, Oh does this sound familiar! Same thing happened to me a few years back. It ended up being bolts in the differential coming loose and catching on the rear housing. Two or more bolts were broken in half laying in the bottom of the transmission and one was part way out keeping rear axle from turning only one rotation each way. Just about two or three feet movement of tractor in each direction. The differential housing was cracked where the bolts went through too. The transmission needs to be opened to see how bad the damage is. I was lucky in that I had a spare transmission from a 518H and just had to swap the hydro pump and a few other parts. If you search on my old posts I think I posted some pictures of the damage I had. Larry (hummod) Share this post Link to post Share on other sites
champ97 0 #4 Posted July 17, 2013 Thanks hummond for the quick response looks like I have some work to do.. hope it didnt tear to much up.. Share this post Link to post Share on other sites
clemedc 29 #5 Posted July 17, 2013 I have a 520 H I bought for parts with 600 something hrs on the meter that is supposed to have a good pump and tranny (I do know it needs a left axle seal it seeps) The PO said they pulled the engine to put it on a nicer tractor. if you need something maybe we can work something out. I have never ran this tranny so I dont really know anything about it. Clem Share this post Link to post Share on other sites
champ97 0 #6 Posted July 17, 2013 Thanks clemedc for offer, gonna be a few days before I get a chance to work on it.. Share this post Link to post Share on other sites
squonk 41,378 #7 Posted July 17, 2013 Any one ever have a problem getting the pump off? I have 2 spare pumps sitting on the bench but the pump won't come off my C-145 with the 1100 trans. I bought a whole unit at the show but would rather try one of the pumps first. Got the 4 bolts out and it won't budge. Share this post Link to post Share on other sites
champ97 0 #8 Posted July 21, 2013 UPDATE...Well had time today to figure out what broke, hummond you were spot on,all 4 bolts holding diff gear were broken plus tore up left side end cap, looked up online looks like $85 bucks in parts, thanks for help.. Share this post Link to post Share on other sites
Kelly 1,029 #9 Posted July 23, 2013 I have tons of used parts right here in MI, let me know if you need something send me a PM Share this post Link to post Share on other sites
Forest Road 594 #10 Posted July 26, 2013 Champ and Hummond I'm curious how many hours were on your tractors? Not that I want to but.... I'm considering pulling mine apart and applying some locktite. Share this post Link to post Share on other sites
hummod 0 #11 Posted July 26, 2013 Mine has 630 hours on it. Bought it cheap with a bad valve seat. Previous owner spent a lot to have the valve seat repaired 25 hours previous. All his shop did was pop in a new valve seat and peen the aluminum. it did not last so he cut his losses and unloaded it on me. I had to have a new valve seat made to fit and it was pinned in place. Larry Share this post Link to post Share on other sites
champ97 0 #12 Posted July 26, 2013 Update Got tractor back together just mowed grass worked perfect, just wanted to add used grade 8 bolts with nylock nuts also grade 8 and red locktite. Think it should be good to go. My tractor doesnt have a hour meter but it has a lot of time on it..Thanks for everyones help.. Champ 97 Share this post Link to post Share on other sites