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Evo main sproket seal

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Old Yesterday | 11:42 AM
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Default Evo main sproket seal

I recen̈lly purchased a used evo upgraded to a 27 andrews. i have changed the seal twice both times seal spring faceing in i have a bdl belt drive im Thinking the crank is cuasing the seal to fail any and all answers will help figure this leaking seal out.oʻ⁸
 
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Old Yesterday | 12:33 PM
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Are you sure you are installing it correctly? In the manual for a 1998 softail on page 3-66 it says to install the sprocket shaft seal with the spring facing out (away from the flywheels). That's how I installed mine. Click on this link ( 1997-1998 Softail Service Manual ) and look on page 3-66 at number 4.
 
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Old Yesterday | 12:42 PM
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Originally Posted by cwhite6
Are you sure you are installing it correctly? In the manual for a 1998 softail on page 3-66 it says to install the sprocket shaft seal with the spring facing out (away from the flywheels). That's how I installed mine. Click on this link ( 1997-1998 Softail Service Manual ) and look on page 3-66 at number 4.
He mentioned Bdl.. open belt drive they often say flip it… personally I don’t think it matters. Is there too much oil in your bottom? Too much pressure? Is your check ball screen upside down? Are you putting it in dry or with a lubricant? Is it going in straight? Does the main seal surface show scares or damage?

I use a smear of Rtv on the metal outside of the seal and a touch of white assembly lube on the inner rubber.
 

Last edited by Rains2much; Yesterday at 12:48 PM.
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Old Yesterday | 10:30 PM
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Default Seal

Originally Posted by cwhite6
Are you sure you are installing it correctly? In the manual for a 1998 softail on page 3-66 it says to install the sprocket shaft seal with the spring facing out (away from the flywheels). That's how I installed mine. Click on this link ( 1997-1998 Softail Service Manual ) and look on page 3-66 at number 4.
I have 3 in bdl belt drive so it says to insert that seal spring in to keep oil in correct me if im doing it wrong
 
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Old Yesterday | 10:45 PM
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Default Main engine oil seal

who has the fix for this seal 3rd time replaced seal and spacer each time but still leak please some suggestions all or any. I thank you all
 
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Old Yesterday | 11:30 PM
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You could also try the Evo forum here: https://www.hdforums.com/forum/evo-84/
 
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Old Today | 03:20 AM
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You need to add a signature line for your year and model with those letters Harley tags it with.

Is it leaking so bad, it's overfilling the primary?

I replaced one damaged whe alternator spline broke.

Be sure your installing seal in correct direction. My sleeve ran the seal toward one end.
it did have a groove in it. I just flipped the sleeve.

Be sure faces that the sleeve go against are not damaged.

Make sure engine vent system is correct.
 

Last edited by Jackie Paper; Today at 03:30 AM.
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Old Today | 07:01 AM
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It would help to know year, model and mileage.. Including all engine modifications.....
I would start with a leak down test on the rings and check to make sure the breathers are working..
 
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Old Today | 08:28 AM
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FYI I combined the "main oil seal" thread with this one. They appear to be about the same seal. Easier than having people toggle back and forth between 2 threads on the same topic by the same poster.
 
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Old Today | 08:43 AM
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Originally Posted by Rains2much
He mentioned Bdl.. open belt drive they often say flip it… personally I don’t think it matters. Is there too much oil in your bottom? Too much pressure? Is your check ball screen upside down? Are you putting it in dry or with a lubricant? Is it going in straight? Does the main seal surface show scares or damage?

I use a smear of Rtv on the metal outside of the seal and a touch of white assembly lube on the inner rubber.
OP you never answered, I’d start with these questions, also confirm if you use a lubricant when installing, add hotrod98’s line of thinking about the breather. All of these things can cause there to be too much pressure on the main seal and cause it to leak.
 
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