Starter motor spinning free, not engaging

[dan cata]

Hi all,

 

So.. I have a friend that has an k1200gt, 2003, servo, etc.

The battery was weak this spring so he tried to charge it, then, when he was to start the bike, he kept the button pressed for way too long. Then he called and told me that the starter motor spins freely and does not engage onto the flywheel.

 

He took the starter off and opened it up, all is in good condition. The problem is that I don't know where the bendix is on these bikes, the lever that engages the starter motor to the flywheel, since the starter motor is perfectly round.

 

Is this system located somewhere else? Or does the engine spin the starter spindle at all times?

 

If anyone could give me a hint, I'd really appreciate it.

 

Thanks,

Dan

[nldaniel]

Dan,

 

The Brick series engines don't have a bendix. they rely on a one way clutch to disengage the starter motor from the engine.

 

This clutch resides inside the engine, more specifically in the intermediate housing which also houses the alternator drive and the clutch.

 

The starter motor spinning without the engine turning over is generally due to sludge in the mechanism of the one way clutch.

To acces the clutch is major surgery, as the gearbox, alternator and intermediate casing have to come out.

 

one thing to try is to place the engine in gear and bump it to the rear. This may free up the components and allow it to be started (once).

 

The trick is to get a flushing agent in the engine, then get it started, if all else fails by bump starting it. Once it runs allow it to idle for 20 minutes or so, then drain the oil and replace the filter. This hopefully gets rid of the sludge in the clutch, allowing it to resume normal function.

 

If that fails it's time to consider digging deeper...

 

HTH, Daniël

[dan cata]

Hi Daniël,

 

Yes, after further investigating this online, I have found out the mechanism for the starter engine. It's way more hard to work on, than on my R1100RT...

 

I'll let my friend know about bump starting the bike. If that won't work, I'll tell him to get the bike to my garage and will open it up myself. I have changed a clutch once on a k12rs, so I don't think it's going to be too complicated, only time consuming.

 

Anyway, thanks a lot for the idea to jump start it. never thought of that. And also, an important advice is that I can fix this by just removing the gearbox and final drive + rear wheel. I thought I had to take the whole engine off the frame for this job.

 

From your/others experience, might there be something broken inside? Or just stuck? It would be nice to know if to order parts before opening it up, not to wait more for parts to arrive.

 

Once again, thanks!

 

Dan.

[nldaniel]

Dan,

 

Two more things: The service manual for the K1200 does tell you to remove the engine to remove the casing.

I've never seen a clutch broken, but plenty which were sludged up. On the other hand, seeing how much work it is to acces the mechanism on an 1200 brick, I might consider replacing it just to be safe.

 

The other: Make sure your friend reassembled the starter motor correctly. I remember a story at the dealership I once worked, about a guy who managed to get the motor to spin the wrong way round ,therefore never engaging the starter clutch.

I'm not convinced that this was a true story, but worth a moment to check, before getting deep into the engine.

 

HTH,

 

Daniël

[duckbubbles]

The other: Make sure your friend reassembled the starter motor correctly. I remember a story at the dealership I once worked, about a guy who managed to get the motor to spin the wrong way round ,therefore never engaging the starter clutch.

I'm not convinced that this was a true story, but worth a moment to check, before getting deep into the engine.

I actually saw that happen at my local dealer (K75). Mechanic was deep into the intermediate case, starter problems. He put the starter together wrong and installed it. When it wouldn't engage, he disassembled and reversed the sprague clutch. Then the engine would turn over but not run. I noticed that it was sucking at the exhaust outlet. He had to disassemble everything again to get it right. A hard lesson to be sure.

 

For my part, I've seen it a thousand times- you are hip deep in a problem, can't seem to figure it out when someone else not involved can walk up and point out what is wrong.

 

Frank

[dan cata]

Hi,

 

I told him to jump start it, then he called back, telling me that one of the two persons that pushed the bike almost pissed his pants when he heard the backfire )

 

Sadly, this did not cure the issue. The starter is still not engaging. He will bring the bike to me and I will take it apart and change the whole assembly with an k1200rs donor bike.

 

About the casing that holds the starter and alternator... What is between that one and the engine? A gasket or some silicone paste? I could not find this info from realoem.com, but to be honest, I did not check with the manual either Yet!

 

Thanks,

Dan.

[duckbubbles]

Intermediate case is sealed with some sort of sealant, as far as I know. I had this problem a while back. Putting the transmission in 2nd gear, engine off, rolling backward and popping he clutch until I could hear the starter turn kept me going for a while. It was slipping intermittently and usually this would be good for several subsequent starts. A different engine cured this.

 

Frank

[Paul Mihalka]

When I had my old style K bikes, (K75, K75RT, K1100LT), I knew about the problem of the starter one-way clutch slipping when gunked up. So in my bike once a year I added a hydraulic valve lifter loosening snake oil to the motor oil for +/- 1.000 miles. Never had a problem again.

[dan cata]

Ok, will try adding stuff to oil before dismantling everything.

 

If that does not work, my question is: can I open that rear side of the engine while still attached to the frame? Or do I have to take it off the frame?

 

Dan.

[SailorJean]

Ok, will try adding stuff to oil before dismantling everything.

 

If that does not work, my question is: can I open that rear side of the engine while still attached to the frame? Or do I have to take it off the frame?

 

Dan.

 

I read the whole thread and "I think" that there is a mis-understanding.

 

For the sludge cleaning (of the oil) to be effective, you need to:

1) add a certain amount of the cleaning-additives to your engine oil (do not overfill above MAX mark)

2) Start the bike with the bump or push start method

3) ride the bike for at least 100 KM for the cleaning agent to do its job

4) flush the engine oil

5) repeat steps 1 to 4, at least one more time before choosing to open the engine

6) put back normal engine oil once the problem is solved.

 

If you plan to open the engine, because the steps above did not solve the starter-clutch problem, you really need to get a shop-manual. The BMW service manual (available in PDF format on a CD) is fairly expensive and not very detailled. The other manual on the market is made by CLYMER and covers the k1200RS (1998-2004) the K1200GT (2003-2005) and all K1200LT - you can get this on Amazon (approx $US 45) or order it directly from automotive bookstore.

 

Having used both, I would suggest to get the CLYMER. Without those diagrams, instructions and pictures you are totaly blind and will loose more money by guessing. Do not try to save by not spending $US 50 on this book - you will regret it.

 

I do NOT work for CLYMER and I do NOT get a sales percentage on this ;-)

 

[dan cata]

Still searching for possible oil additives around here to get inside the engine. Your options may be various around there, but here, nobody seems to know of such a solvent

 

So in case I do open up the engine, can someone please enlighten me on what parts need purchasing? In this link:

 

 

are parts 2 3 4 and 5 sufficient for such a job? Or is this clutch located in another area of microfisches?

 

Also, I'd like to thank you all for taking the time to read my posts. It's really hard to imagine what's in there without prior opening the bike...

 

Dan.

 

[duckbubbles]

4 and 5 are actually the sprague clutch. I'm not sure if 3 is the whole assembly. Unless it is heavily worn, just cleaning out the sludge trapped in there should do. The newer ones have circumferential holes to allow oil to escape by centrifugal action to keep it operating, the '03 should be this way. Regular oil changes should keep the problem at bay. Be SURE to note how the spragues are installed. If you reverse them, they will not grip in the correct direction.

 

Frank