how much yamabond?

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pythonregius24

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I just finished installing my transmission, crank back to the upper case. Before reinstalling my bottom case, how much (how thick) yamabond should i apply in the mating surfaces?and i found 6 acorn nuts for the bottom, can anyone tell me where do they go?
 
When I apply Yamabond, I use a thin coat, like paint. Anything more is overkill and just gets squeezed out anyway. To apply, I use one of those metal handled acid/flux brushes with the bristles cut about half way down. A few dabs of sealer along the joint then spread it out and "paint" it over the entire surface. The brush can be cleaned with solvent afterward and re-used many times. It will become one of your "special tools".
 
On mine. 1,2,3,4 are all acorn nuts.

Other 2 must be under the sump plate. (wrong, not there, checked manual)

Looking in manual...

Like you didn't find anything in the manual and it's been too long since I rebuilt mine.
 
Mine has one @ #12, under the left side cover . Don't know where the 6th one goes .....

StarterGears2.jpg
 
Good stuff 5Twins, I knew you would have a picture.

One lost acorn yet to be found.

I'm thinking somewhere under the clutch cover... maybe not.
 
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Yup - just a thin smear of Yamabond applied with a paint brush. Don't forget the dowels, and don't forget fresh copper washers under those 'special' acorn nuts.
 
ok! Thanks everyone! hopefully tonight, ill be able to finish up the bottom and work on installing the pistons, do you guys metal polish the piston heads after cleaning?
 
New picture just to be one up on 5Twins. ha ha ha (same just more of it and I labeled mine.)

Come on guys, someone knows where that 6th acorn goes.

Another thought. There's copper washers involved so there must be oil galleys near by.

Must be near another shaft that has oil delivery and the bolt passes through.
 

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Yes, the rest of the nuts and washers are regular ones, plus a few bolts and washers in the top half at the rear. But all are regular metric bolt and nuts.
 
I checked the Haynes Manual and there is 1x Acorn nut missing and 1x too many plain nuts shown on page 31 fig 1.2 so thats no help.

the German tightening sequence seems to show fixings 1,2,3,4 & 5 as domed nuts so if the 6th one fits under the left side cover that should be all 6 hopefully .?

I'm dreading closing my cases.... I keep finding things to do to put it off lol:D
 
Just make sure you do a dry-fit first. Double/triple check the bearings to make sure they're properly seated on the locating pins. People have cracked their cases because they missed that and forced the cases together.

Should basically take no effort to have the cases completely closed. The nuts should not be used to actually close the cases.

Double check for the thin shim at the end of the transmission shafts - sometimes it is missing. And if you've got $50 burning a hole in your pocket put the taller 5th gear on if you haven't already. This is your only chance to do that.

You've clearly replaced all the seals?

The shaft for the starter motor is back in place? Make sure you put the retaining clip on the side to keep it in, as otherwise the shaft can slide back out and drop the large gear off inside your engine - then you're opening it up again.

Oh, and put on your 'double check' list for the top end to make sure the little oil baffle metal clip is in the head. I forgot mine and had to re-do the top end, replace the crushed head gasket, re-do the Yamabond etc.
 
Thanks Gary.

I just looked at mine and finally saw the one under the starter that I couldn't verify before.

Peanut you were wrong, the number 5 location is a standard nut.

I knew when I overhauled mine 7 years ago I made notes where the acorn nuts went but that paper is long gone and so was the memory.:laugh::laugh::laugh:

I'll add this picture to the tech section post as well.

:thumbsup:
 

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Tim of DO THE TON said:
Just make sure you do a dry-fit first. Double/triple check the bearings to make sure they're properly seated on the locating pins. People have cracked their cases because they missed that and forced the cases together.

Should basically take no effort to have the cases completely closed. The nuts should not be used to actually close the cases.

Double check for the thin shim at the end of the transmission shafts - sometimes it is missing. And if you've got $50 burning a hole in your pocket put the taller 5th gear on if you haven't already. This is your only chance to do that.

You've clearly replaced all the seals?

The shaft for the starter motor is back in place? Make sure you put the retaining clip on the side to keep it in, as otherwise the shaft can slide back out and drop the large gear off inside your engine - then you're opening it up again.

Oh, and put on your 'double check' list for the top end to make sure the little oil baffle metal clip is in the head. I forgot mine and had to re-do the top end, replace the crushed head gasket, re-do the Yamabond etc.
Click to expand...

Thanks Tim for the detailed advice.

I triple checked everything. I made sure the bearings are sitting/locked in on their locating pins. The shim at the end of the transmission shaft is present. I wont be doing a 5th gear upgrade( i have a 75 engine), but i will definitely do it on my next engine if this rebuild is successful:D

Yes i replaced all my seals. I did not do the starter motor as i will be going kick-only.

I also made sure that all my mating surfaces are cleaned.
 
You might consider leaving the cross shaft and gears in place for the starter just in case you or someone else wants to put it back on.

The bendix gears on the side and gears under the motor cover can always be put back on later but that internal gear and shaft can't.
 
5twins said:
When I apply Yamabond, I use a thin coat, like paint. Anything more is overkill and just gets squeezed out anyway. To apply, I use one of those metal handled acid/flux brushes with the bristles cut about half way down. A few dabs of sealer along the joint then spread it out and "paint" it over the entire surface. The brush can be cleaned with solvent afterward and re-used many times. It will become one of your "special tools".
Click to expand...

Thanks 5twins! I also bought the acid/flux brush and cut it half way down like you said.
263-BD23CC5E50D4-1125-000001A9C9FB589D_zps80aeee9e.jpg
 

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