I have an early 70s IH 3500a backhoe loader, been sitting for 7-8 months. I started it and went to move it and it won't go forward or backward. It will rock slightly when the pedal is depressed and if I lift the rear wheels they will move foreward and backward with no load. Fluid level is full and all other hydraulics work fine, I drove it to where it is parked with no issues and have not had any trans problems prior to this. I have read quite a few other posts and many have talked about a stuck/bad pressure relief valve or somethings along that line. I don't have much experience with this kind of transmission so I'm looking for a little direction on how/where to start. Pics or diagrams would be nice. Thanks in advance !
I have a manual on the 3400A. It says it is good for the 3500A as well. Sometimes there are interesting checks to determine the source of the problem. I'll give it a look and see what I can find. Do you have a manual ?? I just purchased a 3400A that has some issues but it is a standard type transmission which... I am most happy about. For me, simple is better, as long as it works. Take Care and Good Luck, Gene Pearl River, LA
Thanks, I am going to get a manual but figured I would look for help here also.
I have the 3500 a to it also has the same problem under the floorboard on top of the transmission there is a box about 4" x 2.5" and maybe an inch wide underneath that it has two transmission lines one of the lines in the back if you're looking and from the drivers side the one on the right is reverse the one on the left is forward the one on my tractor loss pressure due to the lock rings and the rubber rings went bad I ordered them they will be in on Friday this week I was told this is one of the biggest problems with the hydraulic transmission I will let you know on Saturday if this worked the parts were ordered at a Jacksonville Florida thank you hope this helps
Old post, but I'm hoping people are still online. I have the same problem many people are posting on the 3500a backhoe: loss of power in forward and reverse with the hydro trans. I took off the small plate on top of the transmission and the seals look good. Nylon slip ring and a rubber o ring. I will replace them anyway. Curiosity got the best of me and while the plate was off and two hydraulic lines disconnected I started the backhoe and moved it forward and backward a bit to see how the hydraulic lines worked. No fluid came from either of the lines or the two lines on top of the transmission. I thought fluid would be squirting out of somewhere. Any thoughts on how to fix this? Thanks.
This transmission is used in International hydrostatic tractors, that aren't common, but are FAR MORE common than the backhoes. Try a search of the IH tractor forums for info, redpower dot com, maybe others?
i recently got a 3400a and was given the tensioner spring in pieces out of the forward revers pump underneath the trans, i am looking at the diagram and have not seen the check valve within yet. my issue was no power forward or reverse. backhoe has power, outriggers, front loader, power steering but the tires only roll if no load on them, there is also no reverse, i cant seem to get the tires to spin for reverse but all gears work. im wondering if the check valve could cause this. i ordered a new spring and went to install but there was one in there. it is almost a centimetre shorter than the new one and had 5 shims behind the spring. i have been reading through the manuals but am struggling to find the right information. does anyone have any insight on this