Transmission rebuild question

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fordt
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Transmission rebuild question

Post by fordt » Tue Apr 28, 2020 5:47 pm

Just slapped the 26-27 tranny together but the thrust space between the clutch disc “basket” and brake drum is only .005 or so with the three .042 spacers, is it OK to get one of the older .025 washer from the parts folks to pick up that extra .017 or so thrust space?


Dan McEachern
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Re: Transmission rebuild question

Post by Dan McEachern » Tue Apr 28, 2020 5:59 pm

Tighten the lockbolt then apply a firm rap to the end of the main shaft using a brass drift or a large soft face hammer until you can slide a .015 feeler between the thrust washers. Don't have the main shaft flange bolted to the flywheel when you do this


Topic author
fordt
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Re: Transmission rebuild question

Post by fordt » Tue Apr 28, 2020 6:11 pm

Hmm, gonna have to wrap my head around that, but I’m sitting in my easy chair and not staring at the bolted up tranny and seeing what happens when I do that...it does take out the wait for parts by mail, and it’s only 4 bolts to take off.....but it does necessitate the engine lift harness....


Kerry
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Re: Transmission rebuild question

Post by Kerry » Tue Apr 28, 2020 6:38 pm

You say a rebuild, so all original parts to this trans? if so the only reason for not enough clearance would be that the first bush, fly wheel end, on the brake drum is not pressed in far enough.


Topic author
fordt
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Re: Transmission rebuild question

Post by fordt » Tue Apr 28, 2020 7:47 pm

Are we mixing up spacers/thrust washers on the main shaft with bushings? But I’ll check that bushing as well as its position in relation to the thrust surface...


Kerry
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Re: Transmission rebuild question

Post by Kerry » Tue Apr 28, 2020 8:06 pm

Maybe I should give some more detail, the main shaft has a fillet grind on it at the flange end, if the bush is not pressed in far enough on the brake drum at that end then the clearance at the clutch basket is compromised.


Adam
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Re: Transmission rebuild question

Post by Adam » Wed Apr 29, 2020 10:24 am

That front bushing has to be pressed far enough into the driven gear shaft that the front end of the bushing is about flush with the front of the driven gear keyways. If it isn’t that far in, then you have likely found your problem.


Topic author
fordt
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Re: Transmission rebuild question

Post by fordt » Wed Apr 29, 2020 5:40 pm

Nothing has worked yet, still have only about .007 thrust/spacer clearance between the brake drum inner face and the clutch pack drum. Is it OK to substitute a .025 spacer under the clutch drum to pick up .017 or should I just find a machine shop to mill .010 or so off?


Kerry
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Re: Transmission rebuild question

Post by Kerry » Wed Apr 29, 2020 6:44 pm

OK, if your happy that all is right with the bushings then it sounds like you have a mix of parts. That being an early clutch disc drum. Yes you can play with the thickness of the washers and I have even removed some off the drum before and even turned off the thrust flange off the early bush and just used that. Do what you must to get your clearance. With an early disc drum you might need a thicker first clutch plate or fit 2 big plates in first to make sure that a small plate will not slip down between the brake drum and disc drum.


Topic author
fordt
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Re: Transmission rebuild question

Post by fordt » Wed Apr 29, 2020 8:03 pm

?? Slipping down between things? I reckon my problem is not being explained good enuff.....can one use this part on a 26-27 tranny and still expect it to hold up with the 2 other .042 washers?
https://www.modeltford.com/item/3320BW.aspx


Kerry
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Re: Transmission rebuild question

Post by Kerry » Wed Apr 29, 2020 9:03 pm

Big brake drum, ok, easy fix, order the 3320/BW. That and 2 original washers should put you back in spec and clutch pack as normal.

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