[Darren69]

Originally Posted by utopia

Regarding the alternator rotor nut ....
On the one hand, I would have thought that 150Nm is close enough to the 157Nm spec as to make no appreciable difference, so you should be fine there. Indeed, my factory manual allows a +/- tolerance of 5%.
On the other, I'm concerned about the length of time that it must have taken to tap out the holes in the flywheel and to make the holding tool. I would have thought that this would have been more than long enough for the previously applied loctite to have at least partially cured and therefore its locking function after subsequent tightening to spec torque would likely have been compromised.
It may well have compromised the levels of applied torque/clamping force too, for that matter.
As this nut is apparently known to come undone in isolated cases, I would be nervous about trusting it in its current condition.
Not that I have any hands-on experience of this area myself you understand .. I'm just speaking theoretically.
Why did you not just clean off the loctite and re-apply after you'd tapped the holes and made the tool ?

While I'm on the subject, I notice that my factory workshop manual (admittedly for a later, yr2001 M750) states that a new nut should always be used.
The Haynes manual makes no mention of this that I can see.
Personally, I would replace the Belleville washer too.

I was gonna mention this but you beat me to it Geoff. It was fairly common for that alternator nut to come loose as happened on my 748 and I beleive it is now included in the service intervals, but wasn't previously. I can't remember exactly the details but there may have been a part change to the washer itself.