m42 ('91 318iS) coolant disappearing

[ck_taft325is]

Now before anyone gets uppity (yes, it's a word I swear), I've searched quite a few threads and most don't pertain to what and where my coolant is leaking from.

I recently purchased this car froma r3v member, and it was a very smooth transaction. I want to be perfectly clear, nothing in this post is against his ownership, maint. or terms of the sale. He's a great guy and sold me a great car.

So! On the drive home from Albany (where it was purchased), I noticed the temp climbing a bit beyond my liking. I pulled over roughly 100 miles from where I started and checked the coolant resevoir. Bone dry and a faint smell of over heating. At first, I wont lie, I was a little irked. I walked too the 7-11 and bought some coolant and distilled water (strangely, they had both). 50/50'd it into the resevoir and bled the system a bit. Topped it off again. Gave the top radiator hose a squeeze and felt a few drips. Took a look and sure enough, fromt right under the resevoir, there's a steady stream of coolant running out. Ended up super glueing it and stopping every 30 miles (on my 300 mile drive) on my way back home. Now, first thing is I can't quite figure out how to remove the resevoir from the radiator. Do I pull the whole system, or is there a some kind of secret "hand shake" to get it off? Second, before I pull anything else apart, is there any ideas on what this could be or where it could be leaking from? Should I do another bleed and see if I can't get it too keep coolant? Currently, after driving from 15 minutes from where I stopped to my house and parking it all night, it's again, dry as can be. This is the ONLY place I can detect any leaking/seeping/weeping of coolant.

My wife would love if I got our new car running as we're currently without until this bad boy is up and going. Any help would be ridiculously appreciated. I'd even consider sending cookies too the one who gives some good advice...

Many, many thanks in advance for any and all advice/hints/tips/tricks/pointers.


Further info on the car:

177,000 mileson the clock
Radiator looks nearly new
Fresh oil changes

Runs FANTASTIC besides this little hiccup.

[Asbradley21]

I'd just pull the whole radiator, it's easier than removing the tank IIRC.

[ck_taft325is]

Here's an update. Topped it off and drove 4 miles to my local parts store for some extra coolant/anti-freeze for in the event I stop the leaking. As I get out I pop the hood and find there's coolant/water on the intake side of the engine steaming off the block and pooling a little under the head. Profile Gasket unless I'm wrong? Coolant went from topped off too half. Topped it off for the drive back and when I got home, no steam or extra coolant anywhere. It was still full as well. Any ideas? Puts a pickle in my plans if it is the Profile gasket. Is this parts list roughly correct for what I'd need to replace: http://www.unofficialbmw.com/all/eng...asket_faq.html ???

Also, still doesn't explain the coolant leaking from the resevoir area unless it's spewing over the front of the engine. I couldn't find any other traces of coolant/water on the front of the car except right on the underside/front of the radiator. I had attributed this too the resevoir weeping, but 'eh. At this point I'll park her and see if you fine gentlemen can give me any direction to head in.

Thanks again, in abundance.

[ck_taft325is]

Would this link, http://www.bmaparts.com/ShopByVehicl...et+Set&mode=PA be sufficient for the gaskets I'll need to replace the dreaded Profile Gasket issue? Anything else I should be looking at while I'm into tearing off the head?

[Michael_B]

Anything else I should be looking at while I'm into tearing off the head?

I just pulled the head off of mine last weekend and the only thing that didn't come in the head set I ordered (from PelicanParts), was a second throttle body/heater gasket. Item number ten in the picture p/n:13541743261 according to realoem.com .

Pulling the head was a pretty easy task and took me about 5 hours working really slow, with only hand tools. Here is a great link that I used when I pulled everything out. http://timthurber.com/tcpg.htm . The only other things besides that gasket that you might consider are the timing components. Mine were fine but I replaced the chain tensioner while I had everything apart, as well as dropping the lower pan to check the upper bolts. Also take a look at all of these hoses under the intake.


This would be the time to change any of them if they look bad. I hope this helps.

[2002maniac]

There are tons of coolant hoses under the intake manifold. I bet they are old and cracked. I would replace them (or bypass them) before attacking the profile gasket.

[twistednut]

When the profile gasket goes, it leaks coolant into the oil. You probably have a crack in the black plastic thing that is attached to the block that connects some of the coolant lines.

[ThaiRacer]

I had this same problem but it seemed that it would leak from my bottom resevoir. Also make sure its not leaking from the bleed screw because the o-rings usually go bad on them. let the car run and let it idle then give it some gas once in a while and see where that leads.

[Slick92GS-R]

check the head for cracks... i found 3 in mine !

[ck_taft325is]

There are tons of coolant hoses under the intake manifold. I bet they are old and cracked. I would replace them (or bypass them) before attacking the profile gasket.

After driving it a few times tonight, ranging from 10-40 miles, I'm leaning towards this. Without rev's, the coolant stays where it's supposed too and I'm pretty sure the smell is from when I rev'd higher (5800-6000rpm) on a previous drive.

I really just hate worrying about the damn thing over heating. Would it be worthwhile to pull the intake and check/replace most of the coolant hoses there? TCPG sounds like a collosal whore to tackle without being 100% sure that's what it is. And given that I haven't seen a drop of coolant in the oil, I'm becoming less and less sure about dropping the $150.00-$200.00 in raw parts + time or $650.00 at a shop.

Waffles anyone?

*EDIT*

Also, after driving I checked the top radiator hose which was hot to touch, but when I checked the passenger side-lower radiator return (?) hose it was cold as a witches nipples. Does this point towards thermostat issues?

[3bvert]

as earlier suggested , I would check all those stinking hoses under the manifold and elimante them, this is a common mod to get rid of all those extra hoses, have nto seen a m42 yet of this year range where those hoses wer either cracked, brittle or leaking
the platic pipe adn o-ring can be a leaker too, but my first guess is the hoses

[jrobie79]

platic pipe adn o-ring can be a leaker too

:up:


check out this thread:

http://www.m42club.com/forums/showthread.php?t=2742

and that plastic piece, if not replaced recently, is probably brittle to even a slight tap with a screwdriver, change it while your under there