1991 318is overheating

I noticed this when steam started to come out of the heater ducts while in traffic. The needle was near the red. On opening the hood I saw signs of
leakage on the oil pan flange area on the left side.
I got the car to a dealer in Glendale (Pacific BMW) and signed up for an estimate. That was $115. What ever happened to the days of *free* estimates?
I got a call from the dealer a couple of days later. They told me that they couldn't see where the leak was and if I wanted them to investigate further it would co$t me another $575 to pull the intake manifold. Mind you, that was on _top_ of the $115, and would still be part of the estimate! Actually _fixing_ the problem was not included.
I've _had_ it with this dealer! They must have a steady line of suckers to keep themselves in business, but I have no intention of becoming another one. >:^[
Anyway, now that I'm done venting, does anyone here know what the probable cause of this leak and overheating problem is? I'm guessing that the car leaked out enough coolant over a period of days or weeks to finally overheat. Once I got some water into it I had no problem driving to the dealer.
So, what is the most likely failure mode for this car's cooling system? TIA.
Tom S
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1) Nice car :-)
2) Join www.bmwcca.org, your local chapter will tell you about a good independant specialiast and you'll get the best car magazine your ever likely to read!
3) M42s have a timing case profile gasket between the front of the head and block. You need to remove the head to replace it. On your car it was made from a poor material and can fail. Normally it goes BIG time, if you were able to top up the coolant and drive again this may not be the problem.
4) If it only overheats in traffic it's maybe just a bad fan clutch.
5) Failing the above it could be the head gasket or a sticking thermostat.

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Thanks, but I'm pretty sure the engine isn't an M42. I think it's either an E30 or an E36 - but I don't know how to tell the difference. 1991 was apparently a weird year; even the dealers can't tell for sure which parts it takes unless they _see_ it - not even from the VIN#.

Thanks for the tip. :^)

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The engine is an M42. The body style for a '91 could be either an e30 or e36. In either case the engine is the same.
Kyle. 98 740iL 01 525i
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Take it somewhere else. The normal way with a 'difficult' leak is to inject a dye into the cooling system then pressurise it with air. This will show where it's leaking from. Without this, on a hot engine, the coolant may evaporate too quickly to see where it's coming from.
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Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
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