My first ever post and I have to start with a problem. Tried starting my 1990 E34 535i Auto yesterday only to hear the loudest, most panic causing noise. Turning over to get started made a sound like a large metal disk spinning freely across gravel - really loud. It sounded to be running freely and momentum slowed it to a stop as the car started. When started it runs no problem (no noises) but boy was that noise loud. Took it to mechanic and guess what - no noise. It's done it 5 or 6 times with me but the mechanic has returned it saying he can't get it to make the noise. It sounded terminal/ expensive to me. Help please.

If the sound continued after the engine was shut off I'd suspect the fan clutch. On the other hand if the noise stopped with the engine I'd suspect one of the belt driven components or possibly a sticking start bendix. I can't remember if an E34 has one, but on a cold start the secondary air pump could make that sort of noise as it fails. It doesn't operate when the engine is warm so there could be plenty of starts where you won't hear it.

Thanks thejlevie. I've had 2 suggestions from mechanics today but they didn't seem too sure and both would be expensive just to find out they were wrong. One suggested the flywheel, the other the starter ring. Not being mechanically minded I haven't a clue. Any thoughts out there?

Starter staying on for a minute after it's started? Could be something as simple as a dirty ignition switch, or a bad starter. If that's it, change it now before it eats your ring gear and you're getting a new flywheel...

back in the day there was a bulliten for sticking ing. switch causing the starter to stick, which in some cases caused repeated starter failure. the fix was to replace the switch and housing.

back in the day there was a bulliten for sticking ing. switch causing the starter to stick, which in some cases caused repeated starter failure. the fix was to replace the switch and housing.

That was just for E36 cars.

As I understand the post, the noise was while actually cranking the engine, and it stopped after the engine started, which would tend to rule out the starter circuit. Most likely the noise was caused by a starter fault.

Thanks to all for interest and advice. Starter motor has now been removed and serviced. Hopefully this is the cure - only time will tell!!

the sib iwas thinking of was 120393(3824) which included E30,31,32,34,36 produced before 6/94 but the auto trans cars didn't seem to have this problem

the sib iwas thinking of was 120393(3824) which included E30,31,32,34,36 produced before 6/94 but the auto trans cars didn't seem to have this problem

I'm thinking of the one for installing a relay into the circuit, which I think was just for E36. Maybe that was part of the same bulletin.