Hi,

Rather than hijack the other thread I started about the K1100 overflow tank, I thought it better that I start a new thread dedicated to my intermediate gear repair. At least, at this point in time, I THINK it is the intermediate gear in the bell housing that has been trashed.

First, a little history. I did an alternator swap a couple weeks back. The new alternator had the coupling adapter too high in the shaft, which pushed the drive dog causing it to bind on the bell housing. The result was a catastrophic failure of something in the bell housing. I am guessing at this point that it is the intermediate gear...I might be wrong.

Fast forward to the present. This weekend I started the strip down to get at the bell housing. I encountered a delay in the stripdown. Seems one of the bolts holding the transmission to the clutch housing is siezed. I'm waiting for tomorrow (Monday) to get an impact driver to release the bolt and continue the disassembly.

Quote from the other thread...

I have had some like that where I have drilled the head of the bolt and then work on it without the trans in the way It's not always possible as you may not be able to move the trans back far enough to clear the remainder of the bolt.

Well, I don't think I'll have ANY problems moving the trans out of the way. This is the bike at the moment...


As you can see, the transmission is most readily removable. BTW, you might just be able to pick out the set of "outriggers" that I built which bolt to the oil pan and which stabilizes the engine on the motorcycle jack. They work very well. They are just a couple lengths of 2" angle iron. The remainder of the bike is on the other side of the garage...


As an asside, the bolt that is giving me grief at the moment is pictured below. It's the one in the centre of the photo ...


So, I'll use this thread to post progress reports and ask specific questions. I'm sure there will be a few because, for me, this is very scary work. I've never before in my life attempted a repair of this magnitude. So, I'm nervous but also excited to learn new things about the mechanics of the bike.

Thanks for viewing.

I'll bet a good whack on the end of that Allen head bolt with an impact tool and the appropriate driver will break 'er free. If it twists off leaving the threads behind then an EZ-Out will take it out after a hole's drilled into the remains.

Thanks for sharing the pix. It's good for us all to see how far the carcass can be separated and then resurrected.

yep i agree ....a swift hit on the head of the offending bolt (use a drift of some kind ...and a largish hammer) can often break the bond and get it to start turning...with out ruining the actual bolt....

othewise( if the allen key is not holding ) after the whack ...there looks enough room to get a set of vice grips on the outer side of the head.

dont forget to slightly attempt to tighten then attempt to release ...many folks forget this option....once the bolt shifts ever so slightly ...the undo process often works

good luck were with ya !!!

I would also suggest heat the end of the bolt with a good hot soldering iron until it is hot enough to sizzle spit then drip a good penetrating oil on it like pb blaster, the heating is to expand air in the thread and when it cools and contracts, hopefully draw the penetrating oil into the thread. Take your time let it soak overnight and as suggested try a slight tighten before the release. An extremely high quality precise Allen driver is required which is a tight fit and when you go to loosen it with the impact wrench push down really hard to stop the driver camming out. You will need to have something solid blocking the frame from moving away from you even the slightest bit, since it only needs to move away by 1/8 of an inch or so and it will cam out damaging the socket.
Regards,
K-BIKE

One thing I have found over the years is to soak some vinegar on the bolt it may not be easy there but that usuallly gets rid of the alumunium oxide that will be binding the thread. When you put it back together use an antisieze like locktite antisieze or never sieze and that will stop it happening again.

After 35 years in the engineering trade I have to go with the good sharp hit on the head with a punch before you undo the bolt. Works 95% of the time.

As for heating it. To get it hot enough you will need a gas torch and will do other damage, so I suggest you don't go there.

SUPER BIG THANK YOU to everyone for your suggestions (and yes, I am yelling). I used a combination of everything suggested and top prize goes to pjjms. It took a few good whacks with a pin punch inserted in the hex hole, followed by 6mm hex key socket on a 1/2" drive breaker bar AND vice grips on the outside of the head ... but it came out. The head is destroyed but bolts are cheap.

Should I go stainless steel when it comes to replacing this bolt?

We call this mechanical advantage.

UPDATE:

Got the intermediate housing off the engine after having a "knock-m-down-drag-m-out" fight with the clutch. I won!!

Anyway, once I pulled the cover, I was immediately presented with evidence of my failure....


There was telltale metal shavings around the ball bearing into which the intermediate shaft is inserted and upon which the alternator pressed. A very quick examination of the intermediate gears showed that no teeth were damaged in the mishap... so far. Phew, AM I RELIEVED! I've brought the intermediate gears inside for a very close examination under the magnifying glass later.

I took off the retention plate and pulled out what remained of the bearing....


I kinda sorta feel that I might possibly, maybe, just perhaps have to buy a new ball bearing.
... and maybe a new thrust washer.
... and maybe a new outer seal.
... and maybe a new O-ring.

BTW, that stringy thing is the seal from the ball bearing. I think it melted in the mishap, right befor the failure, and the molten parts were flung around inside the intermediate housing. I pulled it as a single piece from the inside edge all the way around.

So, if my examination of the gears comes up positive, I think I will have gotten off lightly in this mishap.

amen ...bob ....thank hevens

good luck on the reassembly and clean up.

oh!!! and about the stainless bolt ...my opinion it that they look cool, but i have had more break off when attempting to undo than i would like .....just stick to a well chosen bolt with antifreeze / compound on the threads....

Examined the gears very thoroughly. I'm happy to report that everything looks A-OK. I did notice that all the teeth on the starter countershaft gear are very slightly worn as there is a slight deformation in their profile. This deformation occurs only on the far side of the gear, on the edge farthest from the starter motor. The wear appears to be age related. It has caused a burr of metal to be formed on the edge of each tooth. The deformation does not interfere with the operation of the starter or the ability for the starter to turn the engine over.

Should I replace this gear or just leave it?

Also, on a totally unrelated tack, I examined my main output shaft seal. It is not leaking that I can see; it appears to be intact and doing its job at the moment. I have read conflicting advice from other people regarding changing this seal. I don't have the proper special tools to do the job either.

Should I replace the main output shaft seal as a matter of course, even though it is not leaking and I am not sure of its age anyways (i.e. it may not be original with the engine)?

Well, Rob all things considered I guess it could have been worse. Looks like you've got the repair well in hand too. I'm going out to Portland BMW to pick up shims later today or tomorrow and will talk main seals with the 30+ year expert out there to get his take as he has sold parts for the bikes since new and owned an 85 since new as well.

OG

UPDATE: Ordered all my replacement parts for the repair and reassembly process. Of all things, the bearing that I destroyed is not in stock at BMW Canada. Great! It had to be ordered from Germany with a long lead time. So, here's the good part. I went to a local bearing supplier with the broken bearing and they found out it is a bog standard, commonly available item -- a 6004C3. Any good bearing supplier will have this in stock ... and cheap too. They even searched for the alternator drive seal. Unfortunately, they were out of stock on that item. So, by next week, I'll be in a position to repair the broken bearing, replace the main output shaft seal and reassemble the bike.

Nice find Rob and thanks for passing along the info. I was also informed that replacing the output shaft seal while you're in there is definitely the way to go. Hope you're able to post pics of the process as well?

OG

great news bob ......

dont forget to soak that seal for a few hours ....

im thinking theres lots of standard stuff in our babys .......

the other day, off the shelf bevel box output seal at less than 1/2 the price

cheers

Hey Charlie I read that about soaking the seals on the Motobins site the other night and was wondering why this is necessary?
Thanks for the enlightenment.

OG

not really sure og ....but i have been advised that there are a couple of seals that require this technique .

i guess that the seal itself consists of some form of fibre that reacts to the oil ....i would assume durring storage that it would dryout and become brittle (or is made that way for storage).
and may be prone to fracture if installed in a "dry state "

there will be some folks with "the knowledge " but i can be good at following instruction if i know it should be done .

besides its a long ways in ....and we dont need to go back there for a little weep huh ?

I hear ya mate. I'm just always curious. What other seals besides the cam chain cover needs to be soaked?

OG

I've not heard of seals being soaked in oil before (well not rubber seals anyway), but using grease is common. Most seals have are double lip, one on the outside to keep the crap out and the other to keep the oil in. Filling the small gap between these lips with grease stops the seal running dry. In effect just a bit of grease on the finger run around the inside diameter. Important as the seal will wear a groove in the shaft if it's dry.

I think the old style felt seals needed to be soaked in oil, but they have been gone since the 50's.

Another seal issue I've been reading about is the main output shaft seal -- whether it should be installed wet or dry. The advice I've seen is that the new design main seal needs to be installed dry because the PTFE content of the outer coating of the seal. Do others concur?

Just was out at Portland Motorcycle Rob and Jim said that the re-designed seals are indeed dry fit.

OG

good news og ...it makes sence ...after 20 plus years that we have newly designed materials that make life easier.... thanks for the confirmation .

on my other vehicle i have replaced quite a few seals with that new fangled nitron ....whatever its called (can never get my toungue round that one )
with extreemly good results over quite a few years now.

Yeah, I luv it that BMW continued to improve & update the bits and pieces for the old girls.

OG

The advice to soak the earlier seals in oil was also true for the cranshaft rear seal on the old airhead twins.

However the introduction of teflon lipped seals has now removed the need for this operation.

Mike

Ok, so status at the moment is that I've replaced the bearing in the intermediate housing inserted a new seal as well. I changed the main output shaft seal (much easier than I thought) and am at the point to reinstall the intermediate housing and reassemble the engine.

This brings up a point that I'm hoping someone can answer. When I reinstall the clutch I have to center it. I don't have the centering tool or the lathe to turnn one. I saw Bert's suggestions for alternatives at http://k100rt.aforumfree.com/t1148-clutch-centering-tool#14417. This Papermate pen solution looks like it is just a convenient handle to grasp when shifting the clutch plate about inside the housing. I have a feeling that it doesn't actually register the center of the output shaft. Am I correct?

Thanks for the help.

Hi there, Bert´s solution is perfect, the object of the tool is to center de clutch plate hub with the gearbox´s spline in order to make it easier to install the gearbox, as the gearbox´s spline has to fit in to the hub while the clutch plate is clamped by the pressure plate. With the gearbox installed any minor misalignment will dissapear when the the pressure plate frees the clutch plate when this engages.
Bmw tool is intented for proffesional mechanics.
Best regards
JAP

I think I'll end this thread.

I removed the intermediate housing, diagnosed the problem (blown bearing), fixed the problem and repaired the original cause of the failure (extra washer between coupler and alternator body). So, I'm in the phase of reassembling the bike and will have the machine on the road again soon.

Super big thank you to all those great members who have helped me along the way. Also thanks for following along.

Sorry, last post from me on this topic.

Just an update that I FINALLY got the bike together today. Started up with a little effort as new fluids had to get circulated about the engine. Engine is fast idling properly now, and revs properly. No funny, expensive noises are coming from the intermediate housing either. No immediately apparent leaks to boot. This is all really good news.

I tested the gearing while on the center stand and it is smooth! My spline lube really makes a huge difference in the shifting and clutch effort.

I haven't road tested yet since I have to finish tiewrapping all the cabling back to the frame, and attach the fairing pieces and seat. A job well done and all done within a month of spare time in my garage. I certainly learned alot, especially about not being intimidate by things mechanical when it comes to these classic K's.

Nice work Buddy and thanks for sharing the whole process!

OG

Good to see all has worked out well.

If you give a man a fish you feed him for a day but if you teach a man to fish you feed him for life.

Nice, and some men are never seen again by their wives 'cause they're off fishing.

Great going Robmac. Glad it's gone well and wasn't too difficult or hard on the wallet at the same time!. TWB, I love that avitar. Are you the hear, speak or see no evil.... lol

No, but maybe a bit Dazed & Confused!