Calmchaos

The bolt that holds the tensioner to the power steering pump mount KEEPS breaking.
I noticed that my bolt is an M8 and the PET states that the bolt should be an M10, but and M10 will not fit into the hole.
The PET also shows a bushing for the strut that I also do not have. But only on the side where the bolt keeps breaking.

Now... I was thinking of using a bushing since my bolt is smaller... but if the PET says it should be an M10, then there wouldn't be room for a bushing.

I'm pretty darn confused. And so far 3 12.9 grade M8 bolts have broken off in there.

Maybe the threads got messed up, and that's why I can't get an M8 in there? Should it really be an M10? If so, do I still need a bushing.

This is the strut for just the Alternator, I do not have AC or PS.

((BTW I know "tensioner" is not a real word))

schwank

Welcome to my world... I have broken that bolt like 5 or 6 times on the track. Finally since I no longer have power steering, I lengthened the tensioner arm and hooked it up to the former power steering tensioner stud.

That bolt was my nemesis I tell you.

Calmchaos

Hmm... craziness...
That stud hasn't broken yet? It's it just as narrow as the bolt (or even more so)?

Didn't have any problem with the tensioner not being long enough to be reliable?

How long have you been running like this? I'm about to do the same as you since I no longer use my PS pump.

FRporscheman

I just checked PET (the alternator diagram) and you're right, it says the bolt on the PS mount side is M10, but that's a mistake. The bolt is an M8 with a spacer bushing. If you don't have that bushing, go get one from a junkyard.

In the section showing the AC compressor, it says the left bolt is m8x38, and the bushing is p/n 944 126 127 01.

As far as it breaking a lot, I'm not sure why. Are you making the belt really tight (too tight maybe?)? Maybe your tensioner is no longer straight? My bet is that with the bushing there it won't break any more.

Calmchaos

I did what Schwank said. And I'll see how long it lasts.
My alt. belt is always only tight enough so it doesn't freakin squeal all the time.

I think with the lack of a bushing the sheer force became too much. I think you're right. With a bushing I doubt it would break. But with Eric's idea I don't have to wait for any parts. So, I'll go with that until it fails.

Thanks for clearing that up for me Arash! The fact that the PET said M10 had me THOROUGHLY confused.

FRporscheman

np - good luck.

schwank

I have run a couple race weekends now with the tensioner mounted to the power steering stud like that and no issues. For me the main issue is that there is the remnant of an old bolt in that hole and I can't get a drill in there to get it out until I pull the motor later this fall.

Hell there were several track days last year where that bolt broke and I ran a couple sessions with nothing at all holding the tensioner rod in place. Only the tightness of the top mounting bolt kept the alternator where it was... and I had no issues at all. The belt never even jumped once.