Will not travel forward. Backward is ok. When I press the forward pedal, to travel forward, it depresses 1in and pedal makes an audible clunk like it's hitting something solid. Tractor will slowly move forward, can then step on reverse pedal and travels just fine in reverse. Once again when I depress the forward pedal it stops at 1 in solid as can be. All the linkage appears to be free. What's going on?
B7800 Hydrostatic transmission.
- Thread starter Bargainbob
- Start date
RCW
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Equipment
BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
You feel the clunk in the pedal? Sounds like a linkage thing.
First thing I'd check is the damper in the linkage. They cause some things like non-centering Speed Control (causes stalls) and other wonky stuff.
Here's a diagram of your tractor's linkage - - - damper is 180. Work the pedal or pull it off and make sure it's free in it's working. Kind of like a shock absorber on a car.
Other thought is something's gotten bent and causing a bind....
First thing I'd check is the damper in the linkage. They cause some things like non-centering Speed Control (causes stalls) and other wonky stuff.
Here's a diagram of your tractor's linkage - - - damper is 180. Work the pedal or pull it off and make sure it's free in it's working. Kind of like a shock absorber on a car.
Other thought is something's gotten bent and causing a bind....
Damper removed and all linkage removed. The only linkage still connected is the rod that goes through the frame to the transmission or final drive. Parts all over the shop and the yard because you can't take anything apart without taking the other thing apart… Symptoms have not changed. I guess that means it's probably in the transmission? If so want to buy a tractor in a Box? I can't possibly see how to get to the transmission. It's all inside the frame.
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I may be all wet here, so ignore if totally off base.
But I seem to remember there is a bearing inside the frame that is hard to get to and especially hard to replace. In fact, if I am remembering correctly, I remember someone actually cutting out a small section of the frame to access that bearing. Seemed like a good solution in that case, as otherwise what he did would have required splitting the tractor, from what I remember, to fix his issue. All for the sake of replacing a cheap bearing...
I wish I could remember more about the thread I am referring to. Do not even have an idea of what to search for. Maybe someone else will remember and actually say that what I am thinking of is not the same problem as yours...Perhaps a look at the parts diagram might indicate if there is a bearing in there or not.
Just trying to help...not to send you on a wild goose chase!
If the lever and shaft that extend from the side of the HST unit are tight and moving fully when the pedal is pressed in both directions then Its is likely inside the HST. It may be difficult to see but you need to verify the shaft is turning as this is what moves the swashplate inside the HST.
If all is OK there I would suspect issues in the relief or charge check valves referenced below as item 050. You can remove them, inspect for damage/contamination and reinstall them in the opposite port to see if the problem migrates to the other direction. You van also check the neutral valves items 170 (there 2 even though one is shown. Do the same, inspect and swap to see if the issue moves. I would do one set of valves at a time so you know which one makes a difference if they solve the issue.
If you find any damaged o-rings this is one area where I would not trust getting generic ones at a local hardware or auto parts store.
If all is OK there I would suspect issues in the relief or charge check valves referenced below as item 050. You can remove them, inspect for damage/contamination and reinstall them in the opposite port to see if the problem migrates to the other direction. You van also check the neutral valves items 170 (there 2 even though one is shown. Do the same, inspect and swap to see if the issue moves. I would do one set of valves at a time so you know which one makes a difference if they solve the issue.
If you find any damaged o-rings this is one area where I would not trust getting generic ones at a local hardware or auto parts store.
FOUND IT! Decided today there was no option but to split the tractor. Prior to dismantling it, a friend loaned me a remote camera, looked inside the frame and there is a loose clevis pin laying in the linkage. Spent an hour trying to fish it out, was successful and now shifts from forward to reverse, everything seems good. The clevis pin probably came from another project, but the present project is trying to figure out how to put this silly thing back together. Thanks for the advice.
now you understand why I don't care for the b series. Getting anything done on the transmission is a painful experience. I absolutely hate the way they were designed! BX's aren't much better, they are just glorified lawn mowers is all they are--and a whole lot harder to work on seeing that they have most of the features that bigger "real" tractors have, and in only 25% of the space to put it all. Stuff's just all packed together. Just before I left the dealer I worked at, I had a B2100 that had to be busted open to replace a seal on the side of the transmission. $11 for the seal, and about $1000 worth of labor. Then fighting it back together, 2 shafts, a tube, etc all have to line up in sync and the thing's on the floor, tiny, so only one tech has room to barely get a finger in there to help line stuff up while another guy is pushing the back end into the frame, on a floor jack cribbed with a 6x6 block. No fun! Just before that one I had to split a BX and pull the HST apart because of a leaking trunion shaft seal. Replaced that seal, reassembled, it came back a week later with another leak...not of my doing or the customer's doing, it had like 2900 hours on it in 3 years' time, so they've just worn it out. They buy a new one every 3 years so it was time. 'Course I left the dealer and don't know if they got a new one this time or waited.