B7100HST Input Shaft of HST worn

[FromMissouri2]

I have a B7100HST and the input shaft that goes into the HST unit has the splines sheared off. There is a coupling that goes on this shaft and a pin that holds the coupling from sliding forward/back. At first examination it would appear that this is a shear pin, but there wouldn't be splines on the shaft if that was the case.
The issue I'm currently having is that the pin in the coupler is now acting like a shear bolt and shearing fairly frequently.
My question:

Has anyone ever replaced the input shaft to the HST unit on this tractor, and is that practical to do. I know you'd have to split at the HST, and probably remove the HST but if you open that unit up would you be inviting disaster?
My choices are to live with the bolt shearing occasionally or try to fix it but I don't want to RUIN it...in the process.

Thanks

 

[Egon]

Welcome.:thumbsup::thumbsup:

Do a search on TBN. There is a thread on exactly the same problem.

 

[kuboman]

I have a B7100HST and the input shaft that goes into the HST unit has the splines sheared off. There is a coupling that goes on this shaft and a pin that holds the coupling from sliding forward/back. At first examination it would appear that this is a shear pin, but there wouldn't be splines on the shaft if that was the case.
The issue I'm currently having is that the pin in the coupler is now acting like a shear bolt and shearing fairly frequently.
My question:

Has anyone ever replaced the input shaft to the HST unit on this tractor, and is that practical to do. I know you'd have to split at the HST, and probably remove the HST but if you open that unit up would you be inviting disaster?
My choices are to live with the bolt shearing occasionally or try to fix it but I don't want to RUIN it...in the process.

Thanks

The 'shearbolt' is suppose to be a roll pin and the shaft is suppose to have splines. You are using the bolt to drive the unit and it is not designed for that.
You will eventually break the shaft if you keep running it this way. I would fix it.

 

[Yandaddy1110]

I replaced the input shaft on my BX2200 after breaking off the splined end due to seized bearings on an implement I was renting. Had to split the tractor and pull off the hst, not an easy task but not impossible either.
You might as well do it, that tractor has little value broken. Dealers will want around 2k to fix it. Take your time, and pictures for later reference.
The hst unit is very simple with few parts , but the tolerances are quite high for them to work properly.

 

[Yandaddy1110]

I reread the post again, seems what I had broke was the idler shaft in the tranny on the bx, not the input shaft from the motor.
I think the input shaft would be an easier repair than what I had to do. Mostly removing the hst unit and and then replacing the shaft.

 

[FromMissouri2]

KUBOMAN:


I understand that it needs to be fixed.....that is why I was asking how difficult it is to get that shaft out of the HST once you have the HST removed.....Is it just a matter of removing a clip and sliding it out or do you have to have gears pressed off/on, disassemble the whole thing? Trying to get some feel for the scope of the project.

 

[kuboman]

KUBOMAN:


I understand that it needs to be fixed.....that is why I was asking how difficult it is to get that shaft out of the HST once you have the HST removed.....Is it just a matter of removing a clip and sliding it out or do you have to have gears pressed off/on, disassemble the whole thing? Trying to get some feel for the scope of the project.

I believe you will need to remove the hst and split it as the shaft is held in place on the inside. The hardest part will be removing the unit. As the previous poster said the actual hst is a simple unit but extreme cleanliness is a must for these units. Actual cost if you do it yourself should be quite cheap. The shaft will be the most expensive and the are a few small bearings that should be replaced at the same time.