Technical Alternator belt

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Technical Alternator belt

Oct 7, 2003
Carlisle, UK.
With regard to my squealing noise (which went away and has now returned intermittently), I had a mechanic-in-training friend look at it this evening, I couldn't get the gearbox oil filler cap undone so went looking for other possibilities. He though the alternator belt was a bit loose so decided to undo the holding bolts to slide the unit upwards to tighten the belt. Except with bolts loosened, the unit wouldn't move - only a couple of mm give in either direction. Do we need to take the wheel/ liner off to get it moved or is there some other way? This is an 899 by the way, I am led to believe the unit is different on other engines :)
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How right you are Arc, it is indeed. Plan B then........which is.......I haven't a soddin' clue :(

EDIT - someone has suggested it might be slipping further up on the pulley, is this possible or should we turn our attentions away from this and go back to trying to find a way to check gearbox oil level?
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rallycinq said:
The belt is toothed to allow it to go round pulleys, there are no matching teeth on the pulleys, so yes it can slip. You need to loosten the pivot bolt too, not just the adjuster bolt.



Thanks, might give it another go then. So it should be possible to loosen both bolts and tighten the belt with the wheel in place? I am sure we had both bolts loosened.
If the belt is not tight, then it will move up, but it should move down OK once the bolts are loostened. (I think thats the right way up, its a while since I did one but I think the pivot bolt is at the top on the 899, if not, reverse the above instructions)


Helz, with regards to this and your black leaky stuff at the bottom of your engine. have you checked your rocker gasket as this can leak on to the alternator pulley wheel and cause it to squeak, especially as you change speed. Normally worse just as you pull off. I only knw because i have just solved the exact same thing on my wifes 899sei.

Definitely worth checking. Also the oil can drip down the cylinder block onto the bottom wheel causing it to squeak. Either way i would check your oil leak problem too.

THe alternator has a pinion bolt at the top and the adjuster bolt at the bottom. You should find it moves about 20 degrees around the pivot when both bolts are loosened.