1985 K100 Monkey nuts
I just recieved a set of monkey nut for my 1985 K100 from a aftermarket vendor that I have used before. The nuts will only go into the driven pockets with considerable force and there is no room for the driving tangs. I have not tried lubrication with a lot of force. I just doesn't seem wise. I have checked with another aftermarket that says "Bosch OEM replacement" They have a very good picture that looks like what I recieved. The surviving nuts that I took out are smaller and have a difiernt shape. I have done this job before. Has something changed?
That sure doesn't look right!
I would contact the supplier.
I think the cushions are to be installed with the piece that holds them together over the divider, one cushion on each side of the divider, not completly sure, check a manual. Good luck!!
I think wcycle is correct. You might also flip them in-to-out, so that they fill the annular space without gaps.
Turn em over? Put a divider between the two pieces that are attached to each other. I think. I just did this 2 months ago and I cant remember!
Turning them over made enough sense to give it a try and a look in the Haynes manual (when all else fails) indicates that I had them installed correctly. They are just not right. I have already E-mailed the vendor but don't expect an answer till next week. Thanks for looking at it. I will just have call my friendly local BMW dealer for a genuine part. Some call me frugal. Some call me cheap
Let us know what you discover.
I have time on my hands...found this photo to assure us all you have them in right
[QUOTE=walt3022;742351]What is this part?[/QUOTE]
Here's the fiche picture. The cup (#7) is on the alternator shaft. The cup is driven by the "driving dog" (#10) which lives on the end of the motor's auxiliary shaft. The parts in question are #9 (there are three of them), the rubber goobers that cushion the connection between #7 and #10.
Walt, The official name is Alternator drive cushions or mounting rubbers. However if you want to learn more about them you search or google Monkey Nuts.
I have already gotten an answer from the vendor which states that they have sold 100's of them with no fitment problems. They do require some force and lubrication to install. They would refund my money if I returned them. My anwer to them was;
Thanks for the prompt reply. I really wasnÔÇÖt expecting till next week. With 60 years of wrenching and 20 years of teaching wrenching the best lesson learned is, If it is coming apart or going together easy you are probably doing it right. Force is reserved for ÔÇ£It is already brokeÔÇØ or a friction fit and then you use gentle force. I really donÔÇÖt perceive this as a friction fit. At least it wasnÔÇÖt last time I did it and not yet, unless it is my only choice. I will not return the parts. It doesnÔÇÖt make sense. Shipping has already cost more then the part. I will call it a lesson learned but I am not sure what the lesson is. I will still order parts when need occurs. Harold in Kansas
Thanks Oldandslow for the picture. Those are the monkey nuts that I recieved from the dealer several years ago. (I identify with old and slow and the need to keep our vintage K's running).
OKAY. This my question. Has there been an update in the part? If I order from My dealer will I get the same as I recieved from the after market? Has anyone done this job lately? The difference between the parts is that the aftermarked has a 4 sided profile and that parts that I recieved from BMW several years ago are 5 sided with the 5th side is a short side where to driving tang fits. Look at the pictures in this thread and you can see the difference.
Thanks for listening.
[QUOTE=hhshort;742409]OKAY. This my question. (snip) The difference between the parts is that the aftermarked has a 4 sided profile and that parts that I recieved from BMW several years ago are 5 sided with the 5th side is a short side where to driving tang fits. Look at the pictures in this thread and you can see the difference.
What about touching the new parts to a belt-sander, to shape them the way you want. As you are not returning them, you wouldn't be out anything if it didn't work. Just a thought.....
At this stage I would just get a set from my BMW dealer.
I originally replaced mine on my K75S some years ago. I had had an annoying rattle from the Alt and the IBMWR.org K-Tech pages had a great write up. Mine were the consistency of mud and the Alt clutch cup (#7 above, the part the goobers fit in) had two of three chipped and broken fins. Luckily the cup ran less than $10, probably a bit more now, but as these things definitely wear over time and are subjected to lots of heat it is a good idea to think about replacing them next time you have the battery out if it has not been done in some years, before they completely go and cause the clutch cup to fail. It may seem like a big job but it it is really pretty easy.
As you can see from the pic Mike posted above, you've the goobers installed upside down and over the fins instead of in between them. The fit should be snug but not forced - they should stay in if you turn it upside down but fall out with a shake or two.
The way BMW sources parts for the older bikes means you may get an OEM set with a slight design variation, should work fine though. Please post a comparison pic when you get the OEM ones, I'd be interested to see if there is a significant difference.
The Right Monkey Nuts
I did the monkey nuts on my K75S last year after I went through a "refurbish the electrics" campaign on my 1987 bike - which is better described as "old and fast" as opposed to the the owner (me) who is old and slow. I just ordered the parts from Max BMW and the install was very straight forward and the fit just right. I used a little bit of some slightly sticky silicon grease to hold the nuts in place when I re-seated the starter fins into the cup - I would not consider them to be a snug fit as I typically think of it. I reviewed the procedure on the IBMWR tech site and followed it. AS far as your current nuts, I would do exactly what you proposed - just chalk up the aftermarket "not quite right" parts to a lesson and get the right nuts from a BMW source.