I’ve removed the alternator casing to re-paint it on my 1994 916 Strada and have found a loose bolt in one of the gears. It had not come out completely fortunately, looking at the casing, there is a very slight wear mark in the corresponding position where the head looks to have been rubbing against it. Not sure if the cover has been off previously or not, I assume it has, but there’s nothing else untoward inside, everything’s very clean. Is it just a case of re-tightening the bolt (advice on correct torque very welcome). Thanks Jonathan
That appears to be the starter motor to sprag clutch gear retaining bolt. Considering that the bolt appears to have almost completely come out, is there potential that the gear may have been insufficiently retained and thus could have damaged the bearing behind, or may have caused some damage/wear on the teeth of the sprag gear? I would want to remove it and check behind it to see if there’s any damage. Did you have any starting issues?
Thanks - the bolt wasn’t out that far, but was certainly loose in the thread as I could see it wasn’t fully home and I easily undid it by hand. No starting issues though. On closer inspection, the gear is secured with a circlip, so can’t move on the shaft even with the bolt removed, there’s no sign of any damage or wear - albeit that’s only visually inspecting it with everything in place. I have noticed the starter motor looks fairly recent, or at least not 30 years old, so I wonder if the bolt was removed when that was changed, although it doesn’t look like it needs to be. Any idea of the torque for that bolt?
From the workshop manual, it would seem 8 - 10nm with Loctite 222 which should be a medium strength variety.
Is there any axial float of the two gears without the bolt installed? If so, there maybe wear on the shaft.
Thank you After reinstalling the bolt and gently nipping it up. there’s no axial play at all, just end float of about 1mm before the circlip stops it. Hopefully I’ve dodged a bullet by deciding to repaint the case!
