bolts sheard holding prop to gear box

Mon Aug 15, 2011 9:16 pm

Don't know how the hell this has happened But the 4 bolts gear box side have totally sheared in half leaving it spinning and clanging. Looked on oem site but couldn't find part numbers for the nut and bolt. Any ideas? and am I likely to find anything else fooked there when I start sorting it?

Mon Aug 15, 2011 10:25 pm

Prop to gearbox? There's a rubber dughnut there with 3 bolts to the prob and 3 bolts to the gearbox, prop to diff has 4 bolts though.

http://bmwfans.info/parts/catalog/E30/2 ... _mounting/

Mon Aug 15, 2011 10:48 pm

I counted 4 bolts though a connecting peace from the prop on to an X shaped section gear box side?? all 4 bolts had sheared off?? . this is a tec1 sport based C2 2.7 so don't know if they were any different? don't think they are?

Tue Aug 16, 2011 7:32 am

There are 4 bolts holding the prop to the diff

Prop to gearbox end definately has 6 bolts :

the gearbox flange has 3 bolt holes where you bolt the rubber guibo to it and then a further 3 holes where the prop bolts to that.

If you definately are talking about the gearbox end of the car do you have this :

Tue Aug 16, 2011 9:31 am

capri_rob wrote:
If you definately are talking about the gearbox end of the car do you have this :

But hopefully in a bit better condition!
Initial thoughts are that the nuts just weren't tightened enough (if at all), someone has fitted 8.8 grade bolts instead of 10.9, or, depending on what parts have been fitted, it's possible to end up with 10mm bolts in 12mm holes.

Tue Aug 16, 2011 12:36 pm

thanks guys. Looks like I cant count then

I cant gain access to the car again till the weekend as I had to leave it some ware when they failed. Think I worked out the cause. Had the rear sub frame replaced by a garage and they removed the prop so guess the bastards did not tighten them properly

new nuts and bolts on order from BMW should be here for the weekend. Am i likely to find anything else damaged?

Tue Aug 16, 2011 1:01 pm

It probably wont have done the centre bearing any favours if the prop has been flailing around under the car and would definately be worth replacing the rubber guibo if its as knackered as the one in my pic.

IIRC there are 2 different lengths of bolts so you'll need 3 of each and they will only fit one way - there are arrows on the guibo but I still did it wrong the first time and had to undo it and start again halfway through the job.

Tue Aug 16, 2011 1:53 pm

Think I'd be having a word with the garage, bringing such phrases as "trading standards" and "engineers' report" into the conversation if necessary.
There's a locating pin on the front of the prop. that fits into a rubber bush in the gearbox drive flange which should have stopped the prop. flailing around. This bush isn't designed to be a bearing, so check that the pin is still a nice tight fit.
Morale of this story: If you want a job done right, do it yourself.

Sat Aug 20, 2011 1:14 pm

Thanks guys. It was only flaying for a matter of seconds. left the car there and got it towed 1/2 mile to the oldie's house. Prop was a tight fit when I pushed it back in. Only needed to replace 3 of the bolts as the other 3 were still intact (guess they did not undo these) 3 new bolts locktighted in as she's rolling again