B8200 HST forward and reverse pedal issue

[ecook280]

Ok, so I have been dealing with this issue since I got the tractor and until now its been livable, but digging post holes over the weekend it really got to me, the pedal for forward and reverse on my HST doesnt return all the way to the middle when you let off of it, so it tries to keep creeping forward or back depending on which way you were going last, if i manually put it back in the center with my foot its all good and doesnt move, the shaft has been greased and seems free in both directions, so what makes it return to center? an internal spring somewhere? Any help or thoughts would be greatly appreciated

 

[Breeze]

You've got a spring and a bearing associated with the neutral holder, neutral rod. There are multiple pivot points between the pedal and the transmission.

Either somebody there is out of adjustment or more likely somebody there still needs cleaning and lubrication.

A lazy man's fix is to apply the parking brake while drilling, with the transmission in neutral.

A Workshop Manual for one's tractor is worth it's weight in gold.

 

[birddogger]

Yes, a spring somewhere. There's a flat arm with an inverted "V" at the bottom, in that "V" a bearing on a spring loaded lever pushes upward; this is what returns that arm to the neutral position. So that spring may have fallen off or broke, or that "V" could have a load of guk at the apex making the neutral point rather vague. Work the motion pedal and follow the movement, remove foot boards and access covers as needed.

 

[Breeze]

Looking at the tractor from the pedal side, the spring is well above and forward of the pedal.

"As the HST pedal is depressed to forward, the HST holder is rotated, then the swash-plate is tilted by the trunnion shaft and forward traveling speed increases. Then, the swash plate is returned to neutral with the neutral holder arm when the pedal is released. The ball bearing on the neutral holder pulled with the neutral spring seats the detent of the neutral holder arm so that the neutral holder returns to neutral."

"Machine will not stop in neutral position"

"Speed control linkage is out of adjustment or sticking - Repair or replace linkage - adjust neutral adjuster"

"Neutral valve defective - inspect or replace neutral valve"

There are two neutral valves, one for forward, one for reverse and they are located on top of the transmission case, aft end.

I'd still bet that either your spring is disconnected or more likely the linkage is fouled somewhere.

 

[ecook280]

Thanks all, I have a service manual but it was loaned to a friend, got it back today and tore into it this evening, even with the pedal assembly and swash plate removed, the inverted V doesn't return to center and it creeps, I ran out of daylight tonight so I will dig back into it tomorrow, the spring is intact so maybe just that roller is froze up, we will see. There was a ton of play in the pedal shaft where it attaches to the swash plate, looks like it loosened up and the previous owner just kept using it, the parts are soaking in the parts cleaner tank over night, I will see how bad they are worn and if there is any hope of taking the slop out, may just have to weld up the corners of the hole and regrind them so it fits tight on the shaft again.

Once again thanks for the input, it is more than appreciated.

 

[jcansler]

I had a B7100 HST that had the same creeping problem. I don't know if your model will have the same adjustment to the HST available or if it is in the same location as was on my B7100 HST. On mine all the linkage was adjusted and working correctly and I still had the creeping issue. I found out there was a plate about 1"x 3" that is held on by 2 bolts located behind the HST pedal about 12" if I remember correctly. Once you remove the cover plate there is an adjustment nut that you loosened then turned the slotted bolt left or right with the rear wheels raised and making sure the tractor is in 2 wheel drive and the front end chocked . You turn the slotted bolt left or right until the rear tire rotation is stopped then you tighten the nut. The adjustment bolt is very sensitive so it doesn't take much to turn it too much so you have to pay attention the the rear wheel movement when they stop turning it is adjusted correctly. You may have to adjust this several times to get the creeping stopped. I hope this may help you...

Joe

 

[motorhead]

My B7400 had that issue before I sold it. The V plate has a small ball bearing race that had broken. I was able to access it by removing the floor board and opening the center frame box enough to replace it. Otherwise I would have had to split the tractor. Best to look at the part breakdown page to see the parts involved and where to locate them on the tractor.

 

[murky]

I have the same problem on my B8200HST. It's not too bad, but enough that I consider it a safety issue. I'll be eagerly following this thread and look forward to hearing your resolution before I dig in.

 

[ecook280]

Well I found the culprit, problem is its sure not an quick easy fix, every linkage from the pedals to the trans is junk, the links are fine but all the plates instead of having round holes have oval holes, there is so much slop in the linkage that when the roller bearing centers itself in the V which should be neutral, its not. That is why it creeps in which ever direction you were moving last, its not pulling the linkage back to center or neutral. Adjusting the neutral position would fix one direction, maybe, but not the other and probably make it worse, just something I have to live with for now until I can tear everything out and try to repair the plates, I am thinking make a template off the original plate, weld the hole shut, grind it down flat, use the template to mark the center of where the hole should be and drill it. I know the tractor is old and parts are hard to come by, so I think this fix is about the best way to go.