Countershaft Bolt massacre

[bakerboy]

Last weekend I started the job of taking out the transmission to do the "Black and Decker" fix on the dogs of 2nd and 4th gears. Anyways, after removing the clutch I found what appeared to be a bolt (it had been wore down horribly and damaged). After scratching my head for a minute I began to see the wear marks in the case from where the countershaft bolt had backed out and been ground down from the spinning of the transmission. Maybe this is why the guy I bought it from was having "shifting issues". The bolt head had been completely honed into a point and only a 1/4 inch of threads were still visible along the bolt shaft. The rest had been mangled.

As my luck has it, I have been able to find the part number from Yamaha, but it seems NOBODY carries this one bolt (which has been used in many different models of Yamahas).

Yamaha Bolt
SKU:90105-10085-00
Bolt, Washer Based

If anybody knows better places to look than I please please please let me know.

I wouldn't mind finding a metric bolt either to replace it, however I don't know the size of the original bolt and the threading. What I have left to go off of isn't much.

[GAXS1100SH]

Here's your bolt

Looks like they have one here, Just type in the part # in the parts search ,Hope this helps.

Thanks, Steve

http://www.lawnmowerpros.com/Yamaha-Parts-Search.asp

[Ivan]

I have had that happen several times. Took me a while to figure out why it would back out. The result was the gear on the other side of that bearing had been reassembled with an extra one of those very thin washers, I'd call them shims, and it made the counter shaft essentially too short. All in all this means the bolt should tighten down on the end of the shaft and not the inner race of the bearing. If that isn't right even red loctite with primer isn't going to keep that in.

If you can't find another bolt, get one with the right thread that says "10.9" on the head and see if you can get a machinist to fab up a washer on the lathe. Some stainless steel should work ok. The only critical thing is to keep the protrusion down, as that bolt could get into the gear on the back of the clutch basket. If you really want to get fancy, have the machinist make a counter bore the right size for a socket head screw. Just make sure that socket head screw is the 10.9 or better grade.

[trbig]

Sounds like you've got it all figured out, Ivan. Why don't you make a few for us? Let's see.. maybe an hour or two a bolt machine time.. then you can offer them on here for what you have into them and get griped at for trying to cover your cost?

The only thing I might add... is you need to make sure that bolt is hard enough to do it's job, yet IF it backs out again, soft enough to where it doesn't chew up that gear on the clutch basket that eats on it.


Tod