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.

[les]

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.

By the size of the puddle, that looks like one of two things.  Either the race walked in far enough to damage the 5th gear seal, or the pulley nut is loose and it's leaking around the quad seal.  Either way, it's all in the same area.  Yes, it's possible that there is a leak between the large seal and the pulley spacer, but the other two are more common.

[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.

By the size of the puddle, that looks like one of two things.  Either the race walked in far enough to damage the 5th gear seal, or the pulley nut is loose and it's leaking around the quad seal.  Either way, it's all in the same area.  Yes, it's possible that there is a leak between the large seal and the pulley spacer, but the other two are more common.

Hey les. Wound up being the pulley nut was loose. S&S race so no walking. Replaced with all new seals, new spacer & 3 guyz nut, red loctite on threads and smear behind the nut. We shall see. Not 100% sure of the cause fornut losing clamping force. Socket head bolt was intact on the super nut.

[les]

It's nothing wrong you've done, IMO.  That damn pulley spacer seems to sometimes collapse, and the result is the stack gets loose.  Sounds like you've done a good repair and I'm betting no problems from here.

[TN]

Another baker main seal leaking, installed dd7 last year with around 15k miles on it. Installed the timken bearings set on the low end of specs, used the white spacer to set endplay. I did ignore it for some time but it was time to address it, what a mess, did not pull the gears as everything seemed fine except for the leak. I tightened the sprocket nut per service manual vs baker instructions this time and final crank to 45 degrees. I'm just a parts changer but getting plenty of on the job experience lately. 

All buttoned up and ready to ride.

[les]

So, the DD7 comes with the Grudge Box bearing as part of the kit, or did you add that?   When you replaced the seal just recently, did you also use a new Baker pulley spacer?  Just to be clear, are you saying that the Grudge Box bearing had 15K miles on it when it started leaking?

[jmorton10]

Before switching to a grudge box I had a dd7. At that time, the dd7 did not come with the gb bearing although I believe they do now.

~John

[TN]

So, the DD7 comes with the Grudge Box bearing as part of the kit, or did you add that?   When you replaced the seal just recently, did you also use a new Baker pulley spacer?  Just to be clear, are you saying that the Grudge Box bearing had 15K miles on it when it started leaking?

The DD7 did come with the timken bearing main drive gear by request and a few dollars, I didn't replace the spacer but did put a new oring on the end that came extra with the kit, the spacer looked fine no grooves but I could tell where the seal was riding. On hindsight I do wish I got a new spacer but too late now. And yes to failing at 15k miles. My factory seal made it 58k+ miles as I saw about the TT-391.

Anyhow I just wanted to put mine on the list, I inspected the bore and old seal but saw nothing out of sorts. I hope the issue is solved, I hate messing with that sprocket nut. I've got 75miles or so on it since the repair. We'll see.

[les]

Thanks for that reply.  It seems that when we see this failure, it happens in the range of 15K-20K miles.  Not a happy situation and concerns me.  I have an extra new set of seal, spacer, and o-ring hanging on the wall of my garage, just waiting for it to leak again, but that won't be for another 10K miles at least because my last fix was about 4K miles ago.

I've also seen where one lip of the seal rides to close, and perhaps over, the edge of the spacer.  Mine did not do that, as the two wear marks were fairly centered towards the middle of the spacer when I took it apart because of the last failure/repair.  I've resigned myself that this WILL happen again.  Just a matter of time.

[les]

A picture of the wear marks on the one that leaked in 20K miles.  So, this one was not due to one lip being too close to an edge.  Maybe Baker should stop anodizing their spacers?

[autoworker]

Good old Baker.Lots of great ideas with proven results.

[les]

Generally, I've been happy with the Baker products.  I've used:

DD6
Their throw out bearing (I've seen OEM's totally destroyed and pieces on tranny drain plug)
Shift drum
Tranny shift lever
Grudge Box bearing for OEM six speed
Grudge Box gear set

I had the trap door retaining rings cave out on their early DD6, however Baker replaced with a brand new DD6 with the improved retaining rings.  That tranny held tight with my 114".  This Grudge Box pulley spacer is a concern though.

[TN]

My first attempt to fix failed. I went back in and replaced spacer, new pulley, used a Jims meganut, tried to contact 3guyz about their nut but I got no answer and the Jims was available quickly, clutch basket as the stock had some broken splines. So far so good. Also went with the S&S race and stock bearing as my baker high torque bearing left a mark on the mainshaft, wasn't there on first attempt.

When tearing down I did notice the stock lock plate had signs on movement at the bolt slots. I still hate dealing with that big nut and removing the Jims will not work on my method on removing the stock one. Hopefully that won't be for a long time.

Got over 3k miles on it since latest fix.

[Hossamania]

One of the tips for removal was to face the socket so that the surface is flat, taking away the slight roundness at the "teeth".

[Norton Commando]

One of the tips for removal was to face the socket so that the surface is flat, taking away the slight roundness at the "teeth".

I agree; great tip.

[TN]

Follow up

The install of my DD7 was 2 1/2 years ago and if you look at the main drive bore at 3 and 9 o'clock you'll see three small marks where I pulled the main seal, my scoreboard. I really thought I had it solved the last time but here I am again, about 15k miles later. Spent $90 at harbor freight on a corded impact wrench, best $90 I've ever spent on a tool, that nut doesn't bother me now.

[TN]

Took her all the way down, I originally used the white spacer (.102) to set end play, my notes says it was .0015. when I checked it after tear down I was getting .0035-.004. using the same equipment 

[TN]

Got some more parts from Baker, I used the yellow spacer (.100) to set end play, Looks to be right at .001. The spec is .0005-.002.

[TN]

Got to here today and was a good stopping point. I'm just following up with my experience and I have learned a thing or two here but I'm still just a parts changer. Any suggestions are welcome. Will prolly do an inspect of my cam chest while she is on the table, got 25k mi on the build.


Forgot to add that before I took the gear set out I put the clutch hub nut on the end of the shaft and checked runout, damn near perfect.

[les]

Looks like a perfect repair.  I'll also repeat my reply #32.

I have an extra new set of seal, spacer, and o-ring hanging on the wall of my garage, just waiting for it to leak again, but that won't be for another 10K miles at least because my last fix was about 4K miles ago.

[TN]

First time I set end play I used 75-140 gear oil on the bearings and race, this time I used a light gun oil. The new specs are .0005-.002 which isn't much different  but gotta be a reason for it.

Here is one of my specialty tools. 

[FSG]

this time I used a light gun oil

there was a similar process I was involved with years ago where the oil to be used was spec to be 'clavus' .......  felt like slippery water