B21 Hydrostatic Drive not centering

[Friar Tuck]

Greetings folks! I can make my B21 go forward of backward by pressing the appropriate peddle; however, I have to play with the two pedals to get it to stop. Not good. the dealer suggested I replace the Damper HST and that this will likely fix the issue. I have my doubts. I have the new part in hand but as yet have not taken it out of the plastic in case I need to return it. Anyone have any thoughts on where I should start? Reverse pedal goes almost to the floor before there is any resistance.

 

[troutsqueezer]

The damper is a good place to start.

I would also check the linkage from the pedals to the speed control rod.

There is also a return spring that presses the neutral holder arm into the neutral holder which does come off now and then. Unfortunately, it is not easy to access. In fact, you almost have to split the tractor to reach it. Most folks will cut a hole in the floor board, reach their hand in and replace the spring that way. I have been there and done that one. Best way to cut the hole is with an acetelyne torch or similar. When done, tack weld a plate over the hole.

Beyond that, you can tweak the neutral adjuster which is located next to the damper.
I haven't done it but the directions are as follows:
Disengage the front wheel drive.
Lift the rear of the tractor and run the engine at low idle.
Slightly loosen the neutral adjuster set screw.
Rotate the neutral adjuster clockwise so the rear wheels turn reverse.
Rotate it CCW until the wheels stop.
Put a mark on the center frame aligning the groove on the adjuster.
Rotate it CCW until the wheels turn forward.
Rotate it CW until they stop.
Mark the center frame aligning with the groove on the adjuster.
Rotate the neutral adjuster so that it is between the marks and tighten the set screw.

Finally, Have a beer.

 

[100 td]

Beyond that, you can tweak the neutral adjuster which is located next to the damper.
I haven't done it but the directions are as follows:
Disengage the front wheel drive.................and tighten the set screw.
Finally, Have a beer.

Funny thing, I was looking underneath at my pedals today thinking I should pull everything off and grease and adjust it so it returns properly..... but I skipped all the steps above and am now having a beer!:beer:

 

[Egon]

Visually check out all the linkages and the centering mechanism with someone one to work the pedals. Then grease/oil well, work the linkage and proceed from there.

If the centering mechanism is a roller centering in a v notch make sure the roller is in the proper place.

 

[Friar Tuck]

Thanks for all the great Information! I can see that nasty return spring back in there. Hope that isn't my issue but suspect it might be because it feels like there should be a spring to hold it center.I will need to pick up parts and supplies before I tackle this job. Namely beer. I know its the final step but it's a very important one.....lol

 

[Friar Tuck]

I will scrutinize and lubricate the linkage further, thanks. I am able to reach up and work the pedals while I am down there.

 

[TomSeller]

I will scrutinize and lubricate the linkage further, thanks. I am able to reach up and work the pedals while I am down there.

Curious how many hours on yours?

 

[troutsqueezer]

There should also be a zerk on the hub for the pedals. Make sure it has been greased.

 

[sandyc]

Looking over the steps shown above and I would have a lot of concerns about crawling under a tractor that is in gear while being on jacks or jack stands. Just saying! I would think that would be for a dealer or someone with a proper lift!

 

[Friar Tuck]

hours are 0000.0. Only because i have just replaced the broken tack. Old one was 2240.8 Everything is greased and lubed. My issue is it moves too freely. There is no resistance on the reverse pedal until it is barely an inch from the floor. I need to get into the center frame to see what is or is not going on in there.