Shovelhead transmission sprocket way too tight after install

[hubsripz]

Hey everyone been trying to find anything on this but cant figure it out. So i just replaced my main shaft seal and but in the L key, then put on my sprocket and sprocket lock tab/nut and after torquing (105-120 according to manual for late 1978) the sprocket is way too tight and wont even budge. Did I mess something up here? Even tried a much lower torque at 60 ft lb and it was still way too tight. Please help! Thanks.

[hubsripz]

just tried it without L key and same issue. Did i maybe push the new seal too far in? i used the cork, a new spacer, and new seal. the seal sits just a bit further into case past being flush.

[Dragstews]

Think I'd be taking a hard look at the new spacer ..

Make sure it has the same dimensions as the old ...

[hubsripz]

are there different width spacers for different year ratchet tops?

[Dragstews]

Yup ..

Yo Jim, wanna fill him in on what the Mo-Co did from 77-up ... ??

[JBinNC]

Yup ..

Yo Jim, wanna fill him in on what the Mo-Co did from 77-up ... ??

You would put that on me!

'77 - '79, spacer is the same dimension as the earlier spacer, but without the key slot, so no key is used.

'80, maybe late '79, and '81,a new seal and spacer. Also, if it's a chain drive, there is a washer added outside of the seal under the sprocket. The washer is not used with the belt pulley.

'82 - '86 there are different width seal spacers for chain or belt final drive. In those years there are 4 or5 different spacers, depending on the year (if I remember correctly). The seal is different than the '80 - '81 seal that did not work well at all.

For the OP, the cork will usually prevent the seal from being pressed in too deeply, but may rub the OD of the spacer. With the sprocket nut torqued down, if you have end float of the main drive gear, you are probably OK. No end float is NOT OK, and you get to start over. Do you have a seal spacer that has the notch for the key? (I assume you do since you mentioned it.) Technically, that's the '76 and earlier spacer, but it should work (dimensionally the same).

Jim

[JBinNC]

Note: you mentioned the manual for '78, so I took from that, that the bike is a '78. My mistake maybe.

Jim

[Dragstews]

you would put that on me!

Jim

[hubsripz]

You would put that on me!

'77 - '79, spacer is the same dimension as the earlier spacer, but without the key slot, so no key is used.

'80, maybe late '79, and '81,a new seal and spacer. Also, if it's a chain drive, there is a washer added outside of the seal under the sprocket. The washer is not used with the belt pulley.

'82 - '86 there are different width seal spacers for chain or belt final drive. In those years there are 4 or5 different spacers, depending on the year (if I remember correctly). The seal is different than the '80 - '81 seal that did not work well at all.

For the OP, the cork will usually prevent the seal from being pressed in too deeply, but may rub the OD of the spacer. With the sprocket nut torqued down, if you have end float of the main drive gear, you are probably OK. No end float is NOT OK, and you get to start over. Do you have a seal spacer that has the notch for the key? (I assume you do since you mentioned it.) Technically, that's the '76 and earlier spacer, but it should work (dimensionally the same).

Jim

Took out the new seal i had just put in to check out the spacers, here they are. new one on left, old on right. old one seems to have a cut out area on the back side. other than that the spacers seem to be identical. am i missing something? do i maybe have to much play in the countershaft? very confused on this one haha. if it helps any, when i took off the primary the sprocket nut was loose.

[Dragstews]

The old spacer don't look to be in all that bad of shape ...
I'd do a polish job where the seal been rubbing and reuse it ...

[Tattooo]

Don't you guys think he should take the trans apart to see how much wear there is on the bearings? Many times that is the reason the seal starts leaking in the first place....................

[hubsripz]

The old spacer don't look to be in all that bad of shape ...
I'd do a polish job where the seal been rubbing and reuse it ...

So i just did a test fit with both spacers to see how they would compare (without the seal in the case). Both spacers when torqued down to 60 ft lb have no issue moving freely. This leads me to wonder, did i drive that seal in too deep, causing the seal to press too much against spacer/case and when sprocket engages it doesnt move easily? Ive seen videos where guys say to get the seal flush, but unfortunately when installing this skipped my mind and my seal sat in there deeper than flush. Thanks for all the help by the way to everyone, takes alot of stress away having others help out!

[Dragstews]

Dang good idea .... ^^

Transmission main drive spacer has an outer diameter of 1-5/8".
Spacer does not include notch for key.
For use with caged needle bearing main drive gear bearing.

FITS
FL late 1977-1979
FX late 1977-1979

[flatman]

Just a shout out to Dragstews and JB for all their help on this board. You guys have infinate knowledge and just plain ROCK

[JBinNC]

Took out the new seal i had just put in to check out the spacers, here they are. new one on left, old on right. old one seems to have a cut out area on the back side. other than that the spacers seem to be identical. am i missing something? do i maybe have to much play in the countershaft? very confused on this one haha. if it helps any, when i took off the primary the sprocket nut was loose.

The step on the back side of the old spacer is wear, because it runs against the aluminum case on the '77 - '79 transmissions. In my opinion, using 80W90 or 90 hypoid gear oil will help minimize this wear. That wear causes the main drive gear end float to increase.

Jim

[hubsripz]

The step on the back side of the old spacer is wear, because it runs against the aluminum case on the '77 - '79 transmissions. In my opinion, using 80W90 or 90 hypoid gear oil will help minimize this wear. That wear causes the main drive gear end float to increase.

Jim

Yes i use 80w90. however, any idea on why the sprocket would be much too tight when torqued down onto the spacer with the seal installed? still guessing i had the seal in too deep, but im not sure if this is something that would affect or not.

[hubsripz]

Just a shout out to Dragstews and JB for all their help on this board. You guys have infinate knowledge and just plain ROCK

Amen bro. this isnt the first issue theyve helped me with. countless other threads ive followed over the years. gods amongst men lol

[Dragstews]

Hey Now !! .... My eyes are green, so I'm only full of shit to the bottom of em ...

[DustyDave]

In an instance like this I usually do something radical! I measure everything new and old if I don't see anything obvious then I put the numbers on a rough drawing and see what doesn't add up.
Dusty

[Tattooo]

Just a shout out to Dragstews and JB for all their help on this board. You guys have infinate knowledge and just plain ROCK

Yep.......... They always have........... Drag for sure but that's what they do for a living..........