Trans Main Shaft Drive gear spacer for pre 77 ?

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Hogey
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Trans Main Shaft Drive gear spacer for pre 77 ?

#1

Post by Hogey »

Can i use the later trans spacer with out the key notch on my early trans (1968) if i turn down the outer diameter to fit cork seal. Also what is a good brand Name ? i see bender cycle are UAS made.
RooDog
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Re: Trans Main Shaft Drive gear spacer for pre 77 ?

#2

Post by RooDog »

Hogey wrote: Sun Aug 07, 2022 12:06 pm Can i use the later trans spacer with out the key notch on my early trans (1968) if i turn down the outer diameter to fit cork seal. Also what is a good brand Name ? i see bender cycle are USA made.
I don't know about the cork seal's function. I don't even know exactly what it does, or if it is even necessary, but then, that is just me.
Regarding the L key and its notched spacer: I see its function and do install them when assembling a spacer/seal package, even if I have to fashion one out of sheet stock to replace a missing one. But, probably some Milwaukee engineer determined it was unnecessary with a properly tightened sprocket, so it was deleted as a cost savings. Make sense? If concerned about it, you could simply cut a notch in the spacer and install a fabricated key. It's not precision work. I wouldn't be too concerned about the cork piece....
....RooDog....

PS: But I remember that the 5-speed tyranny do not use the L key, nor a cork seal... So, maybe they are not necessary after all....
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Re: Trans Main Shaft Drive gear spacer for pre 77 ?

#3

Post by nifty »

Hogey wrote: Sun Aug 07, 2022 12:06 pm Can i use the later trans spacer with out the key notch on my early trans (1968) if i turn down the outer diameter to fit cork seal. Also what is a good brand Name ? i see bender cycle are UAS made.
Hogey,
My 2c

If you care, when you buy a new spacer, check that seal area runs true to ID, some OE and many repops don't. Some are concentric, but loose at ID, which equates to eccentric when everything tightened...roll the dice. Some will scoff, but I haven't yet had a bad V-twin spacer. I also spin new spacers in lathe and polish the seal area with fine wet&dry, then crocus cloth. You can't beat a mirror finish, even if you lose a few microns achieving it.

AS OE INSTALLED IN EARLY BOXES, SEAL NORMALLY FLUSH, NOT LOW, NOT HIGH, EVEN ALL THE WAY AROUND. However, if flush, sometimes outer lip of some modern double lip seals will track over notch for L key, or lip will be proud of later -77 sans-key-slot-spacer (-77 spacer .030” narrower) this is why we press double lip seals .050” below flush, but I first check that there is no danger of seal inner lip contacting outer face of spacer. I have given up using early notched spacers & L keys, whilst the idea of L key & notched spacer preserving the “fit” of spacer to MDG has merit, reality is that if sprocket nut is loose, oil will be pouring out via splines, if all is good and nut is tight, L key is unnecessary. Also, during installation the notch for L key is more likely to nick a new seal and ruin it.

The -77 spacer obviously alters sprocket position by .030", this concerns me less than relationship of outside sprocket face to ends of male MDG splines, this also relates to thickness of sprocket at splines, many AM vary, PBI sprockets are way thinner at splines than OE.

35079-80 WASHER, sprocket spacer, PLAIN, SPACES SPROCKET ONLY, 1.540” x 2.250” ” x 0.050” thick; (Rotary top/cow pie part, but will fit early boxes, installed between sprocket & seal spacer/top-hat; Helps provide rear chain alignment and clearance between transmission sprocket and case, and to keep the sprocket outside face proud of female splines of MDG, use quantity as required.

35231-36 CORK RING for Main Seal:36-E77 (original purpose was to prevent oil leaking past steel "can" outside of seal, inner/rear edge of 35230-39 seal compresses cork slightly against shoulder of case. If modern sealant used on outside of seal and seal installed with press tool, cork ring can be deleted.(as it was in 77) I haven't installed a cork ring in a very long time.

Summary: Regardless of what manuals instruct, or installed depth, Seal must be dead square to bore of case all around; Inner seal lip must not foul spacer, outer tip of spacer must be proud of outer seal lip; installed sprocket must be proud of MDG splines.

Seal Assembly Method: Lubed spacer/tophat seal ring into lubed double lip seal (James sell good seals), if notched spacer, go in at an angle to get notch past lips before full lip compression; sealant on OD of seal, press* in spacer & seal as a unit, until outside of seal 0.050” below flush with case. *on bare case can pull in with threaded rod (but easy to cock) ; on complete trans can pull/push in using clutch nut and custom pusher tool (my preference), or factory tool modified to push seal .050" below flush). Hammering the seal in, even with a tool, will dislodge spacer from seal, highly likely to damage seal lips i.e. ruin seal. Ditto the MDG end seal, I now push them in with custom, accurately faced tube and clutch nut.
Call me fussy.

Nifty
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Re: Trans Main Shaft Drive gear spacer for pre 77 ?

#4

Post by Hogey »

Good Information thanks Niffty :D
Hogey
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Re: Trans Main Shaft Drive gear spacer for pre 77 ?

#5

Post by Hogey »

Got in touch with Ray in Canada and he is sending his o ring spacer fits 41 -E77. there is 5 different size for the trans. its cheaper than Jims
Mongrel505558
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Re: Trans Main Shaft Drive gear spacer for pre 77 ?

#6

Post by Mongrel505558 »

I've gotten two aftermarket spacers and "L" keys where the notch wasn't deep enough in the spacer for the key to fit flush with the spacer edge, preventing the sprocket from seating straight. Had to file the notch.
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