How common is tranny main bearing seal leaking?

[les]

I've done lots of trannys, and of course installed lots of main bearing seals (large seal).  About 20K miles ago, I installed a Baker Grudge Box bearing when I did my 124", keeping the stock cruise drive tranny though.  Last week I noticed a 3 inch diameter puddle of Red Line under the bike.  I see this typically when the fifth gear seal goes because of the race walking.

When taking the bike apart, I noticed that the leak was coming from the large seal.  Not the fifth gear seal.  When I went to drill my small hole in the seal so I can put a screw in it the yank it out, I noticed that the seal pushed inward a bit when I was drilling.

I've never had a leak out of that large seal before, so wondering how common it is.

[Hybredhog]

     Short of a loose pulley nut, not very often. You may have just came across a odd OD on the seal? But you could use some old Permitex #2 (the brown chit) to glues the seal in, as it hardens.

[les]

     Short of a loose pulley nut, not very often. You may have just came across a odd OD on the seal? But you could use some old Permitex #2 (the brown chit) to glues the seal in, as it hardens.

Yeah, I might have to do that with the Permitex when the new seal goes back in.  The pulley nut took me a 4' breaker which I had to stand on, even after I put a torch on the nut.  I'm scratching my head because of all the things I expected to see with a 3 inch tranny fluid puddle, I was surprised by this.

[MikeL]

How does the spacer look? Might want to flip it around and start a new seal groove

[les]

How does the spacer look? Might want to flip it around and start a new seal groove

Totally understand what you're saying about those darn spacers.  I've had my share of seeing them collapse and loosen the stack.  The Grudge Box bearing has a unique spacer.  It's got an o-ring (in a groove) on the side that goes against the inner race, flat and no o-ring that goes against the pulley.  In other words, it's uni-directional.  I did feel around it for a seal groove, but it seemed ok...and that don't mean it's not worn.  But you might be right that it's leaking out of that.  I have to say I never thought I'd see that large seal leak.  Surprise!  ...again.

[FXDBI]

Was it pressed in or drove in with a seal driver?  Real easy to distort and doesn't take much and it leaks shortly after install.  Bob

[les]

Was it pressed in or drove in with a seal driver?  Real easy to distort and doesn't take much and it leaks shortly after install.  Bob

I've got the JIMS seal installer tool.  So, carefully pressed in.  The seal didn't start leaking until 20K miles.

[CndUltra88]

In the 150,00km's on my 02 Ultra that seal was replaced twice in the 5 spd transmission and once in the 6 speed SE gear set...
Was running Bel-Ray because they used a red dye and if it where to have leaked before I sold it, I would have a better idea where to start looking.
Rob

[D-1]

Ive just gone thru the same with a grudge box. Seal leaked at 14,000mi after install. The seal is a Baker part, not the HD 12074 output seal. The inner lip is not as deep as the standard one. Even with the Baker seal, if you install the seal past flush with the case, the lip is very close to the inner edge of the spacer. We didnt have access to a new seal so tried a std one, installed slightly proud of the case....it didnt work. Have the correct seals now to fit.

[les]

Ive just gone thru the same with a grudge box. Seal leaked at 14,000mi after install. The seal is a Baker part, not the HD 12074 output seal. The inner lip is not as deep as the standard one. Even with the Baker seal, if you install the seal past flush with the case, the lip is very close to the inner edge of the spacer. We didnt have access to a new seal so tried a std one, installed slightly proud of the case....it didnt work. Have the correct seals now to fit.

Looks like I found the expert.  Excellent!  I've ordered a complete Grudge Box kit.  (I don't like the cruise drive.  Finally sick of it after 106K miles.)  When I get the kit, I should I use the Baker seal, not the HD 12074 when I put it back together, right?  Is there anything I can do to make this seal last longer when installing it?

[D-1]

It will come with the correct seal. I would make sure you only install flush with the outside of the case.

[kd]

.... set the main bearing up carefully.  They have another spacer size if needed. Stay well within the bearing spec and the stability will help the life of the seal.

[les]

It will come with the correct seal. I would make sure you only install flush with the outside of the case.

Got it.  Thanks a lot!

[les]

.... set the main bearing up carefully.  They have another spacer size if needed. Stay well within the bearing spec and the stability will help the life of the seal.

So, a bit more on the 1 thou end rather than the 3 thou end?

[les]

D-1, can you recall where your endplay was set to with the bike that had a leak at 14K miles?

[kd]

.... set the main bearing up carefully.  They have another spacer size if needed. Stay well within the bearing spec and the stability will help the life of the seal.

So, a bit more on the 1 thou end rather than the 3 thou end?

IMO and what appears to be the suggestion from Baker by them providing a better selection of shims, I would say yes.  .001 is a pretty low end play measurement and .003 is their self imposed upper limit so I think it can be critical to stay near the tight end if possible.

[rbabos]

.... set the main bearing up carefully.  They have another spacer size if needed. Stay well within the bearing spec and the stability will help the life of the seal.

So, a bit more on the 1 thou end rather than the 3 thou end?

IMO and what appears to be the suggestion from Baker by them providing a better selection of shims, I would say yes. .001 is a pretty low end play measurement and .003 is their self imposed upper limit so I think it can be critical to stay near the tight end if possible.

Maybe but if it's like the crank timkens, clearances increase with heat. Lips of a seal can only work within a small range or they break contact and leak at times.
Ron

[les]

Ok.  I set the bearing at the upper limit, so this time I'll set it at the lower limit.  Closer to .001" endplay.

I'm sure learning a lot about the Grudge Box bearing.  Thank you again for my continued education. 

[rbabos]

Ok.  I set the bearing at the upper limit, so this time I'll set it at the lower limit.  Closer to .001" endplay.

I'm sure learning a lot about the Grudge Box bearing.  Thank you again for my continued education.

Not saying it's the 100% solution but to me it makes sense. Depends on the seal design and amount of gription it's set up for.
Ron

[les]

Ok.  I set the bearing at the upper limit, so this time I'll set it at the lower limit.  Closer to .001" endplay.

I'm sure learning a lot about the Grudge Box bearing.  Thank you again for my continued education.

Not saying it's the 100% solution but to me it makes sense. Depends on the seal design and amount of gription it's set up for.
Ron

I have to admit that as I've been thinking about it the 2 thou difference probably does not (should not) make a difference with a rubber seal, but I'm not going to argue with you about it.  Rather, I'm going to take your advice and just set it closer to the 1 thou side.  Like you say, it could only potentially help the situation. 

[kd]

I think that's a good decision Les.  It'll make for a tighter unit.

I noticed my GrudgeBox was a little louder on accel and decel than the OEM 6 speed when first installed. I was set up at about the middle to high range of the .003 max.  As promised by Baker, as the gears wore in it got quieter and now is actually more quiet that the OEM was. The decel side is still there a bit but getting better.  It probably takes longer to break in the decal due to the short periods of decel use compared to drive side. I wouldn't be surprised if the extra support from a finer end play setting would be a little better in controlling gear noise. 

[D-1]

D-1, can you recall where your endplay was set to with the bike that had a leak at 14K miles?

Dont remember 100%, but i thought it was 1-2. I didnt measure the other day, but i will when the correct seal goes in.

[klammer76]

My stock 2002 5 speed went 48,000 miles and never a problem except a slight weep at the shift shaft seal (Mobil 1 75w-90 entire time). When I installed my complete SE OD6 I found the IPB race had walked and was just touching the main drive gear seal. Wasn't leaking yet.

Last Saturday, did a 400 mile day, all good as usual. Go out Sunday and good size puddle under the primary! 14,000 miles on the new SE OD6 It's tranny fluid, coming off the outside edge of the front pulley whether on side stand or up straight. Oh well, in I go next week. The SE has been great, just wonder what is leaking and what was the cause. I did install a S&S tapered race before I installed it. It's always something.

One note, last two times I went out, after riding and pushing around the garage the belt was making a rubbing sound from the area of the front pulley Belt tight as usual after riding. Checked the tension and it was spot on. Interesting to see what I find.

[bteski]

Curious about this I have a DD7 in my 2015 CVO Roadglide built to a 117, I bought the double timken setup for the DD7 & the main drive gear seal is leaking. I have new seals from Baker & will be working on it this coming week. I also have a grudgebox going in my 2012 with a 124.

[ultraglide59]

I just done one last month. The two inner bearings on the 5th gear housing walked together and made the output shaft flop around like a blown bearing.