Seized Alternator

[VAL. H.]

I have a seized alternator on my 05 1200GS. Does anyone know if it's possible to replace the front bearing alone?

I've had the bike from new and know that the alternator works as it should when it turns, before it finally seized solid. £100 odd for an unknown SH replacement, or about £20ish for a new bearing fitted to a known to be good alternator.



Any advice appreciated.


Val.

 

[Pukmeister]

I'd suggest removing the alternator from the bike as a first step to get a look at the bugger, then maybe a soak the front bearing in penetrating oil overnight before mounting in a vice and trying to free up the front pulley.

I suspect it's just a plain bearing that is full of road dust and moisture causing it to jam up like concrete.

 

[Greenman14]

Do a search, there's a recent thread that covers this in some detail. It might not be the bearings that are seized, could be the alternator rotor seized in the stator. Be careful!

 

[Myke Rocks]

Did the alternator sieze whilst laid up,

Or was the bike in use in the few days before failure?
If it was in use immediately prior to failure, bearing probably gone, and easliy replaced.
If bike was laid up for a few weeks,
it is much more likely that there is a rust build up between rotor and stator and this is jamming the alternator.(Since clearances are tiny, a very thin layer of rust will do so).
If it is this, with belt off, just put a spanner on the end of alternator nut and rock clockwise then anticlockwise a little. The rust will break easily.
When it does so, replace belt and start engine. With engine running, blow out the alternator with an airline.
Job done.
(This happened regularly to my Smart fortwo, because the alternator was mounted very low to pick up water on a wet day.)
Myke

 

[Bendy toy]

A blast of ACF-50 or similar between rotor and stator may help to slow down the corrosion


Sent from my phone with mangled spelling

 

[Pukmeister]

A blast of ACF-50 or similar between rotor and stator may help to slow down the corrosion


Sent from my phone with mangled spelling

But not too much or you could wet out the carbon brushes and cause problems with excitation.

 

[mikeyboy]

have a good look at the casing,they normally split due to corrosion.seen a few that have done this,including my own

 

[jez]

Yep, what Mikeyboy says. The casing on mine had split open due to the rotor corroding and expanding.

 

[Bendy toy]

New brushes are cheap enough but a spit case is curtains for the old alternator.


Sent from my phone with mangled spelling

 

[VAL. H.]

Managed to get the bike apart at last

Well I finally found some time to start pulling the bike apart to get the alternator out. What a mess. The casing has practically exploded. Cracked front to back in at least four places.

So, Obviously I'll be needing a replacement. But there is a bigger problem. Thankfully the three securing bolts for the alternator came our easily. However, the ten mill nut fixing the power lead to it is seized, but probably ok to get at once its out. Where by lies the biggest problem.

The front shock absorbers bottom bolt has rounded off, just enough to push the bit out when pressure is applied. It's not completely seized, but is very stiff. Even after a good soaking. Working the bolt back and forth got it round about one and a half turns, before it rounded.

Any ideas where I go from here? Is it possible to undo the shocks top nut and drop the forks enough to get the alternator over the top maybe? Is there another bit that is just fractionally bigger than the 50 Torx, a Star drive possibly?


Val.

 

[Smug]

Use a flank drive socket on the rounded off bolt. You should be undoing the nut rather than the bolt.

 

[VAL. H.]

Use a flank drive socket on the rounded off bolt. You should be undoing the nut rather than the bolt.

Thanks, I'll have to Google a Flank drive. Never heard it it. There is no nut on the lower front shock mount on the 05 1200s. It threads straight into the wish bone.


Val.


https://www.google.co.uk/#q=flank+drive+socket Hmm, unfortunately that's the part not fitted to this particular bolt. Thanks for your consideration though. It's tother end I need to get a grip on though.

 

[Pukmeister]

Val, the front shock lower bolt is loctited into the wishbone, you need to apply heat with a hot air gun to loosen the bite on the female threads in the wishbone.

Simply forcing the bolt chews up the dry loctite into a hard adhesive which binds the threads very tightly which is probably why yours seized whilst undoing.

Can you hammer a Torx bit into the rounded off bolt head in order to undo it (with heat), then buy a new bit and bolt to replace it later once the bolt is released.

 

[Roymondo]

Oh Lord! Now there's *another* known failure/weak point to fret about!

 

[The Grey One]

Oh Lord! Now there's *another* known failure/weak point to fret about!

What, you mean owners not knowing what they are doing? Applies to every bit of machinery built by man.

John

 

[VAL. H.]

Oh Lord! Now there's *another* known failure/weak point to fret about!

What, you mean owners not knowing what they are doing? Applies to every bit of machinery built by man.

John

I'm so sorry boys, I forgot to search the archives or seek advice from the experts on how to remove a shock absorber.

Maybe I should be telepathic.




Val.



Doesn't help get the thing out either. Even the Haynes manual doesn't mention the lock tight issue.

 

[The Grey One]

I'm so sorry boys, I forgot to search the archives or seek advice from the experts on how to remove a shock absorber.

Maybe I should be telepathic.




Val.



Doesn't help get the thing out either. Even the Haynes manual doesn't mention the lock tight issue.

I'm not sure if being telepathic will help, not putting so much faith in Haynes manuals might. There is a downloadable version of the of the official manual available. I have a copy back at base I could send you but I don't get back to Austria until next Friday.

John

 

[Pukmeister]

Thinking out loud, if you have an electric fan heater (typically 1kw) you could blow hot air over the wishbone for 20 minutes or so to get it very hot, then try undoing the bolt assuming you get a Torx driver into the bolt head. IIRC the loctite softens above 100C but obviously be careful what else you heat up in the area.

 

[Roymondo]

I'm so sorry boys, I forgot to search the archives or seek advice from the experts on how to remove a shock absorber.

Maybe I should be telepathic.




Val.



Doesn't help get the thing out either. Even the Haynes manual doesn't mention the lock tight issue.

My comment was nothing to do with your efforts to remove the shock!! I was having a semi-sarcastic laugh at the revelation that alternator failure due to expansion of internal corrosion is yet another apparently "known weakness" of the Boxers for the nay-sayers to whittle about

 

[(RIP) Arkwright]

If you don't take it out in the wet and keep it in a heated garage then it shouldn't be a problem!

DAMHIK