Convert 186d to dash/column shifter?

oldgrayfellow · Dec 12, 2011

The first year out (or maybe two years), the powershift lever on the Yanmar 186d was mounted on the "floor", with a large metal bracket/shift gate that surrounds the lever. In subsequent years, they put the powershift lever on the dash, to the left of the column, so it could be shifted with the left hand.
The floor area in the newer style had a sloping piece of sheet metal that angled up toward the engine. (see photos).

Anybody know if this change was done just by adding some kind of linkage rods to the new model, or was it a deeper redesign of the transmission?
I.e., would it be possible to retro-fit a linkage from a newer model onto the older model? I'm guessing the newer 187d also had the dash shift.. what about the grey market 1510?

California · Dec 12, 2011

My advice is forget it unless you can park a salvage 186 next to it and transfer over a whole lot of stuff. The whole dashboard assembly has brackets etc underneath that would need to be moved over. There's a lot of monkey-motion linkage that replaces your shift lever.

Just guessing, but I expect the transmission is identical up to where your shift lever is pinned on.

I removed the sheet metal from my 186D that covers the linkage forward to the dashboard. This way, and with the seat mounted a little farther back, I can swing my right leg across while seated, to dismount from the tractor. I also removed the cover over the steering linkage on the left. This makes space to have both feet on the left platform at the same time - previously impossible. It's easy to see why one of the major improvements on the 187 was the added length between the seat and the firewall.

HoyeTractor · Dec 12, 2011

California is right in that it is all the same up to where the lever attaches.

I can send you a diagram but there is a lot of pieces to make that dash shifter all work properly. Not saying it is impossible but, as California said, it would be very hard without a donor tractor. Going from dash mounted to floor mounted would be easy though.

oldgrayfellow · Dec 12, 2011

California said:
My advice is forget it unless you can park a salvage 186 next to it and transfer over a whole lot of stuff. The whole dashboard assembly has brackets etc underneath that would need to be moved over. There's a lot of monkey-motion linkage that replaces your shift lever.

Just guessing, but I expect the transmission is identical up to where your shift lever is pinned on.

I removed the sheet metal from my 186D that covers the linkage forward to the dashboard. This way, and with the seat mounted a little farther back, I can swing my right leg across while seated, to dismount from the tractor. I also removed the cover over the steering linkage on the left. This makes space to have both feet on the left platform at the same time - previously impossible. It's easy to see why one of the major improvements on the 187 was the added length between the seat and the firewall.

Thanks Calif.

That's about what i expected. Looks like it would be a bit of a challenge.

oldgrayfellow · Dec 12, 2011

HoyeTractor said:
California is right in that it is all the same up to where the lever attaches.

I can send you a diagram but there is a lot of pieces to make that dash shifter all work properly. Not saying it is impossible but, as California said, it would be very hard without a donor tractor. Going from dash mounted to floor mounted would be easy though.

Guess it would be quite a task to move all the stock pieces over.

But it looks to me like the shifting is all done just by controlled simple rotation of the powershift input shaft in one dimension-- there is no qualitative change in the "dimension" of the mechanical input when you move the lever sideways to get through the "gates" (detents) on the metal shift housing.
Since that's the case, and since the input force to shift is so tiny, i wonder why they didn't (or why i couldn't) just use a jacketed cable to run up to the high mount shifter, instead of all the complicated linkages and brackets.

YannyMan · Dec 13, 2011

My guess is durability...

HoyeTractor · Dec 13, 2011

Yanmar did use a cable on their lighter duty "garden tractor" line- like the GT14 and others. I'm sure the cables would just not hold up as long as the linkages that they originally used on the 186.

Attached is the shifter schematic for the column shifted 186.