HST Just Won't Stop, Quit, Woah!

[PineRidge]

HST Just Won\'t Stop, Quit, Woah!

Has anyone with a NH HST ever had a problem with their tractor not wanting to stop once they came off the HST pedal? My TC-40D has less than 100 hours on it and this is what I have noticed to date.

Once I load the transmission going up a slope, if I take my foot off the forward HST pedal the tractor continues forward motion unless I hit the reverse pedal to center the two. This has happened more than once and always on a forward slope. Not a big problem for me since I know what to do but I'm thinking what if someone else had this same problem pulling into a garage and didn't know how to shut it down? My pole barn is on elevated ground and I must admit the 1st time it happened it did get my attention real fast. I was thinking for a second that there was going to be another garage door added real soon.

My HST pedals are free, with no binding and this never happens when the tractor is on flat level ground. If I am traveling on a flat surface and I take my foot off the HST pedal then I immediately stop. If I have cruise control set on a flat surface and kick it off then I again immediately stop.

I never gave it much thought until I read a post today that certain John Deere tractors were being recalled for HSTs that did not want to stop either. Hmmmmmmm.

Anyone else notice any type of problem whatsoever with their HSTs wanting to run away?

 

[paccorti]

Re: HST Just Won\'t Stop, Quit, Woah!

PineRidge,

I used to have the same problem on my TC35D but it has not happened in a while. First, I increased the spring tension to return the pedals to the neutral position. Second, I make sure to keep those linkages greased. Perhaps too a little time loosens things up a bit.

Peter

 

[PineRidge]

Re: HST Just Won\'t Stop, Quit, Woah!

Peter I suspected that the tranny might be tight being a new machine and need some time to loosen up. That is why I have not said anything to this point. But I got to wondering after I saw the JD recall. Maybe nothing to this at all, but I thought that I would throw it out at this forum. Thanks for your reply.

 

[yellowsocks93]

Re: HST Just Won\'t Stop, Quit, Woah!

I would not hit the reverse pedal while traveling forward. You may break something. Try hooking your foot under the front of the forward pedal to lift it up. Just something to consider.

 

[slowzuki]

Re: HST Just Won\'t Stop, Quit, Woah!

Shouldn't be able to break anything with the reverse pedal. The variable displacement pump has to pass through neutral on its way to reverse pumping.

there is always the relief valve too!

Shouldn't stick like that, I suggest the pedal linkage is free but the tranny linkage need lube. It is probably designed to return the pedal to neutral or up, independant of the tranny position, like a cable actuated clutch on a car.

 

[jinman]

Re: HST Just Won\'t Stop, Quit, Woah!

</font><font color="blue" class="small">( suspected that the tranny might be tight being a new machine and need some time to loosen up )</font>

Well, here is a problem I know something about. /forums/images/graemlins/smile.gif The problem you described is partially due to the way the transmission works, but if you adjust the spring as Peter suggested and also keep a roller lubricated, you will eliminate the problem almost completely. I've attached a picture showing the pedal mechanism. I had my operator platform raised up because my pedal mechanism broke, and I had to remove the platform to fix the problem. If you look at the transparent oval to the left of the pedals, you will see the location of the roller that needs the lube. It runs on a large metal piece shaped like a capital "B". That piece is painted bright silver in my photo. To the far left, you can just see the spring that Peter adjusted on his tractor. Both of these are easy to get to from under your tractor platform. I think you will be surprised how much better your tractor will work if you keep the roller lubed. /forums/images/graemlins/grin.gif Let us know what you find.

 

[PineRidge]

Re: HST Just Won\'t Stop, Quit, Woah!

Jim I'll hit the roller with some spray lithium grease tomorrow. I would assume the spring has a threaded rod on the end since you said that it is adjustable. I'm sure I'll be able to figure it out once I roll under the tractor with the creeper. I'll let you know then.

Thanks!

 

[Old_Hickory]

Re: HST Just Won\'t Stop, Quit, Woah!

What would or could you break ?
Do you think something would or could be damaged internally ?

 

[Egon]

Re: HST Just Won\'t Stop, Quit, Woah!

Different type tractor Kubota B7100HST but just for information.

Mine does the same thing. It does have a wobble plate external adjustment to aid in centering the Hst. There are also some internal parts involved that require spliting the tractor. This is where my problem lies. So far economics dictate living with it.

Egon

 

[tc35dforme]

Re: HST Just Won\'t Stop, Quit, Woah!

Jim,

I agree 100 %, but want to add a footnote. On my TC35D, I have had to clean the linkage, before re-lubing. It tends to accumulate some smudgey stuff, grit, and crap. I just clean it all up and re-lube. I know its time to address this when I get that 'Whoa' feeling.

Its definetly more pronounced in the cold ! You know Jim...those -15 mornings /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif