Rick Carter

All packed up and ready to go to Hell after work this morning. After I got to the office I decided to gas up at the station on the corner. I started the car and no power steering, so I thought I'd slipped or broken a belt. What had happened was my crank bolt had backed out and the crank pulley was off. I've called a friend who has a lift in his garage and it will be flat bedded there and hopefully ready to go by the time I'm finished working.

Steve Tacheny

This happened to me twice. It was torqued both times and the 2nd time I even locktighted it. Wonder if it should be Left hand threads

Steve

Mrmerlin

pay careful attention to the crank washer that goes under the bolt head ( the recess faces the nose of the crank)and also if one of the thrust washers ( the ones that ride next to the timing belt gear may have been bent) could cause this to happen, if the bolt was loctited how long did you wait for the loctite to cure ?
and it can also be possible that the harmonic damper might have slipped on its rubber interface to the inner portion ,and is out of balance, or the AC pulley isnt flat or the P/S pulley has a bent mating area

Bill Ball

In the SC kit Andy sold, he intially had people use the stock crank bolt. Tony had one back out. By the time I got my kit, Andy was providing a longer crank bolt, taking into account the additional hub thickess of the kit's crank pulley. For the 2 years and 20K miles I had my kit installed, I had no problem with this, even with open road race torture. No Loctite. If your crank bolt is stock, get a longer one.

Steve Tacheny

How much longer is the super charger bolt. Do you know? It always seemed to me that the stock one was a little too short

Steve

Bill Ball

The longer bolt has a 60mm shaft. Head marks are VIBO 10.9. VIBO is an Italian bolt maker.

Steve Tacheny

Bill

Thanks for the info. Something we can all use.

Steve

Tony

Longer bolt , good TQ, and a small dab of blue loctite for good measure. When you come off boost quickley at a higher rpm the supercharger puts drag on the pulley asembly and tries to undo the bolt IRRC

Giovanni

Stock bolt is 2 1/4" and Andy's is 2 3/4".

Lizard928

Gio, when measureing a bolt you never measure the head.

Giovanni

I learned something new today

Rick Carter

I'm bumping this thread as I'm looking for the longer bolt. Does anyone know where to buy it?

Bill Ball

You need an M18 x 1.5 x 60 grade 10.9. I can't find a good source. Others here have mentioned some comprehensive metric fastener houses, but I can't locate that information at the moment and the Google is striking out for me.

ew928

Nutty Company of all places.

Is this the right spec grade of bolt?
60mm bolt

2nd search hit result from altavista search engine
Haven't touched the Google in a long time.

Rick Carter

I googled and found The Nutty Company then came back to post my search results and found I'm in second place. This is medium carbon steel (Metric 8.8 like SAE Grade5). Is this the same as stock? I don't remember the markings on the stock bolt.

Edit: I see Bill posted it is 10.9 like grade 8 SAE.