Leaking trans input seal...not sure

[The Raven]

Originally Posted by Infracaninophile

Raven:

1. I'd replace. It's a cheap part and easy to do. Did it on mine in 10 minutes.
2. Your pictures are getting much better. A good thread like yours is 10x as nice when we can see how f**ked up your bike is. Are you using the G12?

I just got done with 5 hours of Matt Parkhouse. My R100GS is ready to hit the road to it's new owner.

Tom

Hmmmmm. Must think about this. Any photos on the procedure?

Yeah I'm using the G12 and the eye-fi card. Wonderful setup. The worst part however is taking the photos with my greasy paws.

I do have to give you credit for your careful restoration. In just cleaning my trans up tonight and I went through 24 q tips and the thing is still filthy.... simply amazing

Kind of glad I took it apart...it is kind of f**ked up. Nothing major though. Just a lot of mild neglect and enough problem areas left to make the bike a ticking time bomb for a break down.

[Beemerguru]

Looking at the clutch picture..I'd say you have a leak back there (duh). Drop the clutch plate and flywheel -new bolts for both- and see if the spray is around the main seal or just at the bottom...the oil pump cover.

If OPC, replace O ring and make sure you tap all 4 holes to get the gunk out and clean the bolts too. If not, the bolts will bottom out before they should if you use a torque wrench and the cover will still leak.

If main seal that's been covered here plenty of times.

[The Raven]

Originally Posted by Beemerguru

Looking at the clutch picture..I'd say you have a leak back there (duh). Drop the clutch plate and flywheel -new bolts for both- and see if the spray is around the main seal or just at the bottom...the oil pump cover.

If OPC, replace O ring and make sure you tap all 4 holes to get the gunk out and clean the bolts too. If not, the bolts will bottom out before they should if you use a torque wrench and the cover will still leak.

If main seal that's been covered here plenty of times.

My guess...it's the Oil pump as i did not clean out the threads, nor torque them properly in NM. The RMS has been done before and technically should be fine, though I am prepared to replace again if need be. (Got the right tools this time!!!)

I will ask this question now as I will have to in the future. What is the accepted torque value for the fly wheel bolts and the clutch bolts? I understand there has been some discussion on this.

[Beemerguru]

Don't have any of the manuals in front of me...

Flywheel is around 70lbs. I use blue Loctite.

Clutch cover is either 16ish or 24ish. and the blue stuff again...but that's me.

[supershaft]

I really don't understand why you would use blue loctite on flywheel bolts or clutch cover bolts. The only useful purpose I can think of is if it helps you remember to tighten them in the first place.

I don't think there is any reason to use new 11mm flywheel bolts unless they are buggered up. BMW says the same especially if you use the oiled torque value. 76ftlb dry and 92ftlb oiled. BMW recommends oiling them but I have seen NO issues using the dry torque value with no loctite.

Cover bolts are 21NM. I recommend using an inch pound torque wrench on those. Too loose and they fall out. Too tight and the star washer will split and then they fall out. It's a fairly fine line. If the bolts are real good, I re-use them. ALWAYS use new star washers.

[Mugwest]

Man, i get out of the airhead loop for a bit... same shite different year

I understand though. The bikes have remarkable longevity legs, and so do the questions and 10 billion proffered answers.

Tranny input seal removal has been waaay overstated here. Special tools?

Here they are:

--sharp/thin awl or even an icepick
--hammer
--fine-thread screw of some sort. Some use dry-wall screws but i like a fine thread wood screw
--pair of pliers (Vise-Grips preferred)

Tranny is out of the bike and on on the bench.

Probe with the awl/punch/icepick and determine where the steel collar is on the face of the seal. Find the steel surface of the seal (it's covered in rubber, hence the probing); with hammer tap the awl/icepick smartly into the steel. You will simply pierce it, don't go deep. The tranny input bearing is a few mm's behind that seal. You won't damage the brg but if you whack too hard/deep w/ the hammer you may break off the tip of yr awl/icepick

The steel part of the seal has a tiny hole pierced in it now. THread/screw in the fine-thread screw into said tiny hole, not too deep again.

Get purchase of a few threads of the screw in the hole. Grab the head of the screw with your pliers (or clamp onto the screw head w/ Vise Grips). You or a buddy will hold the tranny solidly and yank the clamped pliers backwards. Seal's out. Took longer to type this than it will take you to do it.


Goo:

Loctite anywhere in the bellhousing is a bad idea. The flywheel bolts certainly do not need it at 80lbs dry/clean torque, and blue on the clutch housing bolts (the weak/strippy 24-30lbs 6mm allen heads w/ the funky 7mm threads) is an engraved invitation to having to drill the heads off every one of those the next time you have to pull the clutch. Rust takes care of the threadlocking there, boys.

Only item in the bellhousing that ever got Loctite on my 3 airheads was the oil pump cover bolts, per Oak. And that was a 50/50 mix of Loc Blue and Hylomar.

I know we shadetrees are raised to think Loctite Blue = 'Security'. There are places, however, where that stuff is flat unnecessary and will only make your head explode later.

MRP

[Wirespokes]

If you've already had the flywheel off and replaced the RMS and OPS, there's a good possibility your leak is from the GUIDE RING o-ring.

Don't forget to line up the flywheel before removal and block the crank.

If the seal feels pliable and not leaking, I'd be tempted to leave it. But they're not expensive and easily replaced - up to you. I've left mine alone (until rebuild time) and haven't had a problem yet.

[supershaft]

Different year but it's the same bike so you ought to know it's going to be the same shit.

I have seen a lot of gouged up seal bosses from people trying to use screws for pulling out seals! Why go to all that trouble? A common, ordinary seal puller thinned a bit for the application is MUCH simpler and faster with way less to go wrong.

80ftlbs is in the ballpark but 24-30ftlb on late model clutch cover bolts is way too much. 30ftlb will just about for sure split the star washers. The torque spec is 15ftlb!

[Mugwest]

Originally Posted by supershaft

A common, ordinary seal puller thinned a bit for the application is MUCH simpler and faster with way less to go wrong.

Elucidate, please. I'd very much like to see the non-BMW/Kurka 'common, ordinary seal puller thinned a bit for the application' that you recommend for removing the input shaft seal from an airhead transmission. Pictures, sir.

Originally Posted by supershaft

24-30ftlb on late model clutch cover bolts is way too much. 30ftlb will just about for sure split the star washers. The torque spec is 15ftlb!

mea culpa, Superman. Had no data in front of me, going on long (fallible) memory which i admit was not acceptable in someone's how-do-I-do-it thread. I will fact-check from now on since i've been out so long. Memory gets displaced by other imperatives

[The Raven]

Originally Posted by Wirespokes

If you've already had the flywheel off and replaced the RMS and OPS, there's a good possibility your leak is from the GUIDE RING o-ring.

Don't forget to line up the flywheel before removal and block the crank.

If the seal feels pliable and not leaking, I'd be tempted to leave it. But they're not expensive and easily replaced - up to you. I've left mine alone (until rebuild time) and haven't had a problem yet.

All those were done including the guide O-Ring. I think it's going to be a matter of getting to the source and identifying it. I don't like risk on something I am going to ride, so will leave the trans seal alone until rebuild time. Like Beemerguru said way back when the spray pattern is not right and there is no hypoid oil.

But this is now....this may change prior to reassembly, after reading toms thread and when I get a package from brown santa.

[supershaft]

Originally Posted by Mugwest

Elucidate, please. I'd very much like to see the non-BMW/Kurka 'common, ordinary seal puller thinned a bit for the application' that you recommend for removing the input shaft seal from an airhead transmission. Pictures, sir.



mea culpa, Superman. Had no data in front of me, going on long (fallible) memory which i admit was not acceptable in someone's how-do-I-do-it thread. I will fact-check from now on since i've been out so long. Memory gets displaced by other imperatives

I haven't found the gumption to learn how to load pictures on this site. The seal pullers are usually KD or Lyle brand and are usually available at most auto parts stores and Sears for $10 or less. They are magic IMO.

[The Raven]

Originally Posted by supershaft

I haven't found the gumption to learn how to load pictures on this site. The seal pullers are usually KD or Lyle brand and are usually available at most auto parts stores and Sears for $10 or less. They are magic IMO.

Hey supershaft,

They sound interesting, if you want and have a photo available email it to me at mobilefreedom at gmail dot com. I'll drop it up on this site. It'll make it easier for you. Photo posting in a PITA unless you do it all the time IMHO

[supershaft]

Thanks Raven but google KD seal puller and there it is. They are available about everywhere. They are so cheap and simple. I usually have about three of them because I have modified a couple for special applications.

[The Raven]

Damn, there are a bunch of seal pullers out there....do a search on Lisle 58430 Shaft Type Seal Puller

I remember pulling the RMS out with the screw and a slide hammer attached to it. Worked well.

[supershaft]

I am not familiar with the 58430 but I know the others work like magic.