Yanmar 186D broken shaft

[HoyeTractor]

Are we sure the shaft was ever originally broken and not just stripped? I'm thinking the original failure was stripped splines, then welded, then re-welded. Don't know for sure though but seems very unlikely that shaft would actually break.

 

[ptsg]

Are we sure the shaft was ever originally broken and not just stripped? I'm thinking the original failure was stripped splines, then welded, then re-welded. Don't know for sure though but seems very unlikely that shaft would actually break.

My thoughts exactly. Usually the splined coupler would be the failure point there.

 

[California]

it's AMAZING that an 18 HP.engine could break that shaft if it was properly made, maybe Yanmar has a recall on it?..

Like I said, ease every hard shift by slipping the clutch a little. The jolt of a full throttle shift spooked me the first time I did it, it felt like it would break something - like this.

 

[radios1]

Like I said, ease every hard shift by slipping the clutch a little. The jolt of a full throttle shift spooked me the first time I did it, it felt like it would break something - like this.

that points to a big engineering failure!. it should never be necessary to slip the clutch, and that also wears it out unnecessarily!.. who does that on purpose?.:shocked:

 

[California]

that points to a big engineering failure!. it should never be necessary to slip the clutch, and that also wears it out unnecessarily!.. who does that on purpose?

Maybe I shouldn't have said slip. Disengage for an instant just enough to reduce shock load. Powershift is a straight mechanical connection, engine to wheels, after the internal clutches engage. They engage instantly at high rpm. Owners have shown leaving skidmarks on pavement at each shift like a modified Mustang or something. Not me!

Shifting down at full throttle as a slope gets steeper is one of the advantages of Powershift. I find this little guy (18 engine hp) is very nearly the equal of my YM240 (24 engine hp, manual transmission) because of avoiding the full stop to change gears many times as I move around in my sloping orchard.

I would much rather split the tractor and replace the conventional clutch ahead of the Powershift, (not likely needed) instead of having to repair the Powershift internals, or face the broken shaft we see here.

To conclude, the Powershift just works. At 40 years old I'm going to baby it a little. Replacing the conventional clutch seems a lot easier than risking damage to the PS or that shaft.

 

[ajaukema]

Im working on 2 scenarios:

1 replace the main shaft, splined coupler and PS pump shaft, but hard to find this parts. I asked hoyetractor, not shure if they ship to The Netherlands.



2 I got a clutch disc, main shaft, splined coupler, PS pump from an 1510, almost identical but sadly different splines.



The idea I have is to have a custom shaft for the PS pump which has 186D splines on the output and 1510 splines on de input side.
Green arrows = 1510 parts
Red arrow = custom, 1510 splines
Blue arrow = custom, 186D splines



Or a splined coupler after the PS pump which has 186D splines on the output and 1510 splines on de input side, not shure if that is possible to produce...



What do you guys think?

Any ideas how to open the PS pump? I removed the 2 bolts and the circlip on the output side, but it doesn't open much further than a couple of mm.
Are some steps missing, or does it need more force?

 

[California]

What about using all 1510 parts, including the pump clear up to including the clutch disc? Even if you have to shorten the shaft, this might be simpler.

 

[ajaukema]

What about using all 1510 parts, including the pump clear up to including the clutch disc? Even if you have to shorten the shaft, this might be simpler.

Sadly not possible because the splines on the output side of de PS pump 1510 don't match on the input side of the 186d gearbox.....

So de idea is to have a custom shaft for the pump:



The green side needs 1510 splines, the red side needs 186D splines

 

[ajaukema]

Last week I got the new shaft for the pump:



From this:



To this:



I rebuild the tractor, put a new hydraulics filter on it and added new oil in the transmission/hydraulics reservoir.


At first the tractor seemed to work 100%, but after a while the powershift give some issues, it wont shift in the reverse and 1st gear.
Sometimes it won't shift and sometimes it takes up to 30 seconds and then it shifts into gear.

I suspect it has too little oil in it.

Got 10 liters, filled the filter first and the put the rest in the reservoire.
The manual says it need 8 liters, but I think it needs way more.
Anyone over here who knows how many liters oil this tractor needs?

 

[KWentling]

I would be looking for a suction tube leak. That pump is setting up pretty high so there must be a tube reaching down into the fluid. A leaking connection or hole in the tube might be close to the normal fluid level and under use it sucks some air. The previous "fix" might have been to add fluid until it quit sucking air. Is there no sight glass or dip stick?