Car died. Alternator?

[Paul in NZ]

the alternator may be ok it might be the voltage regulator(diode??) thats gone...quite possible that you didnt have enough power to crank the engine but the lights are ok(for a while(they draw less than the starter)

[NielsGalan]

interesting about the diodes, fusible link, stereo etc., but none of those things explain the sick sounds the car made before it died. That's what troubles me ...

I'll have a proper look over the weekend, try to spin the various things which the belts drive and then carefully start her up.

I've also noticed what resembles metal shavings on and around the alternator. Could just be crap, and it may or may not "always" have been there, but I'll need to remove the cam belt cover and have a look inside.

I'll report back sat/sunday.

best, Niels the Public Transport User.

[DaveVoorhis]

The 524tds has a belt-driven camshaft. If the cam belt has stretched, walked down the pulleys and started to chew its way through the cam-belt cover, or if the idler has seized, this would definitely explain the noises and poor performance. It still wouldn't explain the low battery.

[NielsGalan]

The 524tds has a belt-driven camshaft. If the cam belt has stretched, walked down the pulleys and started to chew its way through the cam-belt cover, or if the idler has seized, this would definitely explain the noises and poor performance. It still wouldn't explain the low battery.

Yes. The timing belt was replaced a year ago by a proper bmw dealership in Germany. I changed the water pump a couple of months ago, and I needed to loosen the cam belt to remove the pump, but I was careful to mark everything so everything came back together properly. So the belt should be fine.

What's this idler thingy you mention? Is it the thingy that adjusts the tension of the timing belt?

[DaveVoorhis]

What's this idler thingy you mention? Is it the thingy that adjusts the tension of the timing belt?

Yes, the idler adjusts the tension of the timing belt. It should have been replaced when the belt was replaced, but they can fail and if the belt wasn't properly re-tensioned when it was re-installed, it can walk up the pulleys and rub on the belt cover. I've seen it happen on an M20B20 petrol engine

[NielsGalan]

Well, it appears that the mystery has been solved.

After having the alternator checked and it was found ok, I went in and had a look behind the cam belt cover and everything looked ok. I turned the engine by hand a few times and found the engine to be a bit squeaky.

So I check the engine oil level again (after the car has been sitting there for a week) and lo and behold! The problem was .... wait for it .... too little engine oil! Exactly what the car was trying to tell me in the first place. (Insert blushing smiley here)

Upon having this "problem" the first thing I did was to check the oil and it looked fine. But today it was a different story. I pulled around 3 liters of engine oil out of the car. Should be around 6.5 liters in there. Shock and horror.

So now I just feel stupid. I tried to start the car gently after checking the belts and stuff and it started just fine. Power and all. So it appears that the engine has been seized or something due to a severe lack of engine oil.

The engine "seems" to be fine now, but I think the turbo is making a new sound since the ... incident.

Off course I'll be extra gentle and attentive the first couple of days. It's pretty optimistic to hope that the engine can walk away after being mistreated that way, but I'm having my fingers crossed.

Well ok missing 3 litres of engine oil is peanuts! This video indicates that the M21 engine is one durable MF! They're really getting medieval on that engine's ass :-) http://www.youtube.com/watch?v=B4l5PhKhT3U

ps. I regularly check the oil level, and it has always been fine. Where 3 liters of oil just up and went suddenly - that's the question...

[Tiger]

Maybe out through the turbo lines ro burned through the turbo... look for blue smoke or puddle of oil.

[attack eagle]

yep, blown turbo.
check it for shaft play, left right up down in out at the impeller... If there is ANY movement exceeding a 16th of an inch,

even IF the engine is ok> the turbo isn;t.
Don't drive it until you can change the turbo. Ingesting metal shavings from impellers scraping or bearings self destructing is NOT beneficial.


Where 'd the oil go? probably out your tailpipe every time you asked for boost.

[NielsGalan]

So I'm looking at at dead turbo.

Very interesting. After the car had been at a BMW shop in Germany I started noticing a new sound, a high pitched whine. I have always associated this sound with the turbo or transmission, but it can very well have been the turbo all along.

Yesterday when I was missing a shitload of engine oil I talked to my oil-guy and wanted the same grade as the BMW shop had put in the year before. He was appalled by what I told him, as he said that that was way too thin for such an old engine. I think it was called 0w30 or there about, the 0 being the thinnest possible.

Inevitable as my turbo failure may have been, it looks like it was helped along by water thin engine oil.

[Tiger]

Thin oil as long as it is high quality synthetic oil... has better protection and sheer force protection than the thicker one. That's old timer thinking for the old dino oil... yet the thinner oil has better protection than the thicker one in dino too.