Set off to work this morning and had covererd 30 miles when the Battery light decided that it would come on. Not a great problem I thought I can just pull in and check it out. What was disconcerting was I also had a lound crunching/grinding noise. So wanted to get somewhere safe to pull off the road.

Bearing in mind it is 7am and the temp is 3degrees I couldn't see anything obvious so phoned the recovery services (Easier to get recovered and investigate at home bearing in mind i still have to get to work)

I guess the first thing I need to rule out is that it wasn't the alternator brushes crunching and grinding, so will whip the regulator off and check to see what I can see....

The reason for putting this into the engine section is incase it follows onto be an engine fault which would sugest a problem with the Auxhillary shaft... however does the auxhillary shaft also take it's drive from the starter motor when the engine is turned over? The bike starts on the starter without any problems. (well it will do till the battery is flat)

Any simple checks anyone can think of that I haven't kind of detailed above? Or has anyone known the regulator bushes to disintegrate into the alternator which is what I am kind of hoping/expecting...

initial thoughts twincarb

could it be a colapse of the rubber couplings between the aux shaft and the altenator (often known as monkey nuts ) be the source of the noise ?

doesnt explain the lack of charge , but possibly affected the altenator as well .?

got my fingers crossed for you .

Whilst in work today and without looking any deeper at the bike I ordered the rubber bushes and I also ordered a new rectifier so that if they are what has gone belly up then I have them at hand, I am not to sure about what was causing the noise however it was sounding loud with ear plugs in.

Not going to get a chance this evening to start stripping the bike (ok I lie I am heading out there now to see if I can get the rectifier off the alternator!

The noise started after the lamp came on which is confusing... I am thinking that if the rubbers managed to get chewed up then there wouldn't be a grip at all on the alternator to turn it.....

Going to make a coffee and have a look then report my findings back....

TC

Just had a look at the bike... first I whipped off the rectifier....



I then had a go at taking the alternator off.... Lower two bolts off... top one refusing to budge! need to have a think how to attack that bad boy... feels like the allen head has rounded... it's a 6mm on mine... may have to see if I can pursuade a 7mm onto it!

Whilst I was tinkering I could get my finger in to turn the fan which is attached to the alternator... turns without a problem put the bike into gear and turns just as easily... I think I may have got away with the rubbers having disintegrated!

With any luck the parts should arrive tomorrow so I can have a good go on Sunday of removing the offending bolt and confirm that its only the rubbers that have dissintegrated....

I will also put the new rectifier into place as it won't do the old girl any harm at all.

(looks like this should be in the electrics section now! although the alternator is mounted onto the engine)

hmm that could be an issue ... lets hope the drive off the aux shaft has become loose only ,,,but i thought it was keyed in some way ?

Will find out what mess is left behind when I get the alternator off... and of course photos will be posted!!

I don't want to be the messenger of bad news, but I see two possibilities; 1 - rubber nuts gone - this will result in the vanes of the coupling cup and the drive part touching and disintegrating. 2 - the coupling cup is no longer properly fitted on the shaft and has resulted in a gouged/ground shaft.
Hoping I'm wrong here!

I can see where your coming from ReneZ, I was having a look earlier at the possibility of upgrading the alternator to the 50 Amp version which doesn't appear to big a job. I think it's motorworks who do a version with the 50 Amp internals in a 32 Amp body.

The only question is what damage has possibly been done internally, with any luck the damage will be limited to the Alternator rather than within the engine side.

I will only be able to know once I have got the alternator off I am going to have an attempt tonight to see if I can get the last bolt off. But it won't be until about 9pm this evening UK time so don't want to be making to much noise or the neighbours may start complaining!

I am half expecting to see some nasty metal remains when I get in there.... Just hope there isn't the need to strip the engine down....

Below is an image of the Bolt that I have managed to kill the allen key fitting point any hints or ideas on what the best course of action is? (Last resort maybe to get my mig welder from work and then weld an allen key into it!!

Is there any way to cut a slot in it with a small grinding wheel?

Bang in a torx head the next size up - guess you'd need to use a hammer and a drift to drive it home?

following the thread with interest Twincarb. Good luck with it. I've had success with rounded off allen heads by driving a slightly larger torx bit firmly into the rounded off socket.

88

Snap Dave!

..........and add some heat at the intermediate flange where the screw is mounted.

Yep, the Thorx idea has worked for me.

10-Ring the space to get in there is really tight and incredibly awkard with my hands in there I can't see what I am doing apart from looking from the side...

bingo..... MT350Explorer Thats what I shall do I tried to use a 7mm allen key but thats not having any of it...
A T40 or T45 will go in and should get enough of a grip to shift it Job for first thing in the morning now

Will have to be carefull with the heat!

Thanks for the ideas

I am feeling a bit nervous about what I am going to find with any luck it's only going to be damage on the alternator side....

twincarb wrote:Will have to be carefull with the heat!

You don't need to use the oxy welder..........even a 2KW heat gun would help.

giggling away here thinking about borrowing an oxy welder..... now that would take off the head of the bolt at least hehe

You can also use a drill with a strong bit and drill off the head of the bolt, then use locking pliers to unthread the remaining stud once the alternator is off. Had to do this with the waterpump last year. Works great, the bolt is pooched anyhow...

If you are going to do it later put a good dose of penetrating oil onto it If you don't have any make some by taking some acetone nail varnish remover and mixing it 50/50 with Automatic Transmission Fluid (ATF) then drip that on preferably putting some on every few minutes so it can really soak in.

If you can get a straight line onto it buy the right sized high quality Torx bit that fits onto a 3/8 drive, clip it on the end of an appropriate 3/8th extension and then drive the torx into the bolt head by hitting the end of the extension thereby transferring all of the impact shock onto the torx/Allen head socket getting that torx deep in the socket of the Allen. Then avoiding wiggling the torx in the Allen put the drive on the torx and give it a good twist like you are trying to break it loose (which you are) As Stu Ritter the Merc mechanic extrordinaire says twist it like you really mean it. As you do that Don't let the extension angle away from right in line with the Allen.

When you put it back with a new Allen use some blue or purple Loctite on all the threads so as to exclude moisture and air and they will come out easy as pie next time.
Regards,
K-BIKE

Just a thought , would easy outs be any benefit in this scenario?
wishing you every success, TC.

you should be able to get a long and strong screwdriver onto the head of that screw twincarb

what im talking about is to use it like a cold chisel and be able to get a bite into the outside circumference . edge at an angle with a good sized hammer (about 30 degrees from bolt line )...after creating a small divot in the outer casing of the bolt . then get a slightly different angle to rotate the screw . the shock process and the heat generated often let the bolt turn ever so slightly .....once this happens use the torx bit . in any case just getting a good drift in there to shock the bolt end on does wonders .

hope this helps some

That top screw is a bugger to get at other than directly in on top. I would do as Club C said and use an 8mm drill and drill the head of the bolt then grip it with locking pliers and the stub will usually come out easily.
Hint! put the other bolts back in to prevent the drill bitting into the aluminium case and damaging it.

Right I got the top bolt out just needed some persuading from a Torx Bit

Now what did I find....




Well there was me thinking it would be something simple... I then had a look at the mating point which looked solid and turned..... a bit too smoothly as if there was no resistance apart from the bearing it sits on pushed my finger in to feel the bolt that hold's it all in place and it wiggles like a wiggly thing....

Due to the noises it was making and the lack of any resistance I think that I need to strip everything back hmmm wheel off, swing arm off, gearbox off, bell housing off. Then I will be able to report back what I find.



I suspect that the bits shown above are going to be ok....



I am not expecting the above to be in a pretty state!

Can't finish this on a negative.

Those monkey nutz are very worn and would be very noisy and check the nut in the centre of the drive on the alternator if it is a bit loose then there is no drive because there is no key just a tight nut that holds it.

post removed

The alternator side is all fine... apart from the monkey nutz... have new ones here ready to go in. and also have a new regulator/brushes to fit as well.

The bolt part number 11 is shagged! no other description for it.



What part does the bolt screw into?





Got to say the condition of the bolt is a strange one.... The damage thats been caused on it could maybe attribute the noise... need to find a bolt of same size and see whether it "bites" onto cog 9 on one of the eariler pics

I would have expected it to go into a thread inside the splined shaft but it looks to me that the shaft inner diameter would be larger that 8mm. Odd to say the least, I have had a couple apart over the years but cant quite picture what is supposed to be there.
Is there any sort of thread inside the splined shaft.

Computer just crashed as I typed a reply!

Bolt is a m8 x 22 got one here it bites into the thread I am guessing into the first cog on the diagram below, when all the parts are together on the bike I am sure that they mate against the engine case and the bell housing case which would or should mean there can't be any damage inside the engine.

The bike still starts well it did last on Friday without all the extra noise! I am thinking that I could torque up the replacement bolt and start her up with no alternator and check that there are no strange or out of place noises?

Anything else anyone can suggest or think of prior to attempting to start the engine?

Yeah the definition of technology is something that doesn't work properly yet. Aren't they delightful things.
If there is a good thread or useable then I would be putting a new bolt in with some loctite on it and putting the alternator back with new nutz and brushes and see how it is.
I would say that the vibrations set up by lose nutz have caused the bolt to come lose.

I would agree having heard an alternator run with nuts missing its quite the cacophony....but why did the battery light come on....go ahead bolt in and start without alternator and listen...fingers crossed no noise..

Just trying to find my copy of the Clymer to see what Torque the bolt is supposed to be tightened to.... unless anyone has the info to hand...

The only reason I can think that the alternator light came on is without the bolt holding everything together the mating on the engine is allowed to free run so the resistance of the alternator and monkey nutz would be enough to stop the alternator from spinning... That's about all I can think of.

perhaps item 10 spun freely with the bolt no longer mating the splines???

im thinking the bolt has been loose for some time and probably striped out most of the thread in the receiving end ....might pay to put a bottom tap in there to clean up any rounded thread that might be there ...this might give you an idea of the threaded sectional depth that still exists ? then see what happens with the new bolt .

thread locker ? to hold it there for a while at least (as you may not be able to pull up to spec i expect ) maybe just a few pounds of torque ?

could the bolt have backed out creating force to separate the mating monkey nut interface and drive splines

sure would have made some weird noises

thinking aloud

I wouldn't expect them to separate far enough to lose drive and both drive plates are still in one piece. If the spline moved far enough forward to disengage the spline then all hell would break lose and there is no way it would go back in.

Its half past 11 at night and there is all sorts of crap on telly but I am sitting by because this is far more interesting.....

I have put the spare bolt I have got here in and seems to be biting well all the way in. I haven't put thread lock on yet as am going to take the bolt back out so I can check to see what the thread looks like.

I didn't think about running a tap in there first! but depending on how the bolt comes out possibly still will do.

Have ploughed my way through the Clymer and can't see a tourque for the bolt. I am thinking that by the time I have got thread lock on there that will help to hold it in place.

Are you not going to be able to go to bed until I say what happens when I attempt to fire the bike up Klomply!

yep mate you are the best show in town...and I am actually familiar with the area....thanks to Rossco's strange noises which turned out to be a cracked coil.....go figure

Bolt torque would be around 12 - 13 ft/lb

Just worked my way through clymer this time reading properly the part that is being tightened is the Alternator drive dog 29 -37 Nm

I tightened up the bolt but the drive dog still kept spinning which is suggesting something is still amis...

So on with stripping the bike down... I have a couple of hours before I have to get ready for work, with any luck I should have a stripped down and those ahead of the UK time wise will hopefully be able to see whats occurred as you sleep..

Not looking good for these gears then......

[/quote]

I am thinking part 5 which is the "clutch" all the little parts in there and springs.... Once I find out i suspect that an oil change will be in order! can't have lots of little bits of metal floating around....

Hmmm best I get back into the garage current temp 4 degrees and starting to fall!

a balmy 19.1 C here..and raining....and yet another camelot show on telly....how many times can they drag this up...good luck twin carb am really on the edge of my seat...if you were closer I would be happy to help.

Well it's 11.30 here and I am hitting the sack so I will wait till tomorrow for the next enthralling episode of "Screwed".
Yeah I think I can wait.

Thanks for the support..... Am heading back down to the garage see how far I get...

night guys...cannot wait to find out "who did it"

cheers and good luck Klompy

twincarb wrote:Just trying to find my copy of the Clymer to see what Torque the bolt is supposed to be tightened to.... unless anyone has the info to hand...

Hi there, as per Haynes: alternator drive flange/auxiliary drive shaft retaining bolt... 33 +/- 4 Nm
Best regards
JAP

The coupling you refer to only relates to the starter and is not part of the alternator drive, so I doubt if it has anything to do with the alternator shaft running freely. Did your new bolt bottom out in the thread of the shaft instead of tightening the vane wheel? Strange one!
After you bolted it down, did you try to put the bike in gear and move the rear wheel, just to see what happens?

Renez I tightened it up to a point where there was still some resistance but didn't over tighten or take it to the torque thats needed as a final torque and the vane wheel still rotated freely with no sign of any resistance. I also put put the bike into gear and tried to rotate the vane and there was no feeling of resistance.

I was expecting resistance to build up reasonably quickly as the bolt is only 22 mm long. There is nothing stopping me from attempting to tighten it all the way up.

Just had a second attempt this time it tightened up eventually, dropping it into gear turning the bolt the rear wheel turns. Not sure why it appeared not to before. It could be that I didn't give it enough strength! I may have been being overly cautious the first time not wanting to cause any damage.

Just had a look for my torque drive and it's at work only have my big one and the lowest that go's to is 60 Nm which may be a bit to tight for the bolt.

Have taken the bolt out again I need to get thread lock on it which is hiding from me at the moment!!

Feeling a bit silly now and also confused as to why the first time it felt like it wasn't locking even though there was resistance....

No worries mate, we all have those moments of doubt sometimes..... As long as you get her right again!