leak behind primary, suspect main shaft gasket, anyone have tips? 1986 flhtc
leak behind primary, suspect main shaft gasket, anyone have tips? 1986 flhtc
It is pretty much pouring out and I know what it takes to get to it but I am not sure what to order as far as parts, any recommendations for what I should get while I am in there?
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From: Coromandel Peninsula New Zealand
Take it apart, see what it needs and then order the parts, there is no point trying to second guess these things on a bike of that vintage. The mainshaft has a seal and not a gasket, it could also be the Inner Primary seal or even the gear shift seal....do them while you are in there though.
I wouldn't imagine the shift shaft seal leaking as bad as it is, it will leak constantly. Made it home and she was empty after 40 miles. Due to the shift seal near the top of the transmission I wouldn't think it would leak like that, am I wrong?
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From: Coromandel Peninsula New Zealand
You could easily be wrong, if a seal rots and simply falls apart it will leak like a waterfall, if your tranny output seal is shot you may also have a stuffed bearing or the spacer may be scored and has torn up the seal.
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if the splines on the main gear or pulley are worn you will get a serious leak too. if either are worn even a small amount they will have to be replaced. i chased a trans leak for an entire summer and finally figured out the main gear's splines were shot. i replaced it and the leak went away.
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If oil is pouring out, it is probably a loose pulley nut.
Don`t order any parts until you get it apart.
When you go back together, I suggest using the `94 and later parts (upgraded pulley, spacer, nut, lock, oil seal).
As Bagga said, inspect the splines on the main drive gear (the splined shaft that the pulley mounts on).
Don`t order any parts until you get it apart.
When you go back together, I suggest using the `94 and later parts (upgraded pulley, spacer, nut, lock, oil seal).
As Bagga said, inspect the splines on the main drive gear (the splined shaft that the pulley mounts on).
Last edited by Dan89FLSTC; Jul 7, 2014 at 04:47 AM.
Anything specific I should recognize as wear? Hope its just a seal, I hate dealing with that tapered shaft on the transmission, pulling that clutch basket is nerve racking!
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I've had the quad seal between the input and output shaft crap and the tranny oil pours out sitting on the side stand.
Odds are it could be the inner primary bearing race has slipped back allowing the main shaft to very slightly wobble and has taken out the primary seal and possibly the quad seal. There's a solid, single piece inner primary bearing available that some update to.
You won't know for sure until you take off the inner primary.
I pull the clutch basket with a simple "steering wheel" type puller. Tighten it down and give the tighting bolt a tap and it typically pops & slides right off. And don't forget the clutch basket nut is reverse threads.
Odds are it could be the inner primary bearing race has slipped back allowing the main shaft to very slightly wobble and has taken out the primary seal and possibly the quad seal. There's a solid, single piece inner primary bearing available that some update to.
You won't know for sure until you take off the inner primary.
I pull the clutch basket with a simple "steering wheel" type puller. Tighten it down and give the tighting bolt a tap and it typically pops & slides right off. And don't forget the clutch basket nut is reverse threads.
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