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Mendozart
08-16-2008, 03:20 PM
I'm wondering if this is the early stages of bad headgasket? I noticed I've been losing a little bit of coolant recently. About a minute after I start my car, I'm getting some steam exhaust. Usually, I'm right on the freeway, and it will continue emitting steam for about another minute. I've got no coolant in my oil, or oil in my coolant. I'm going to pull my spark plugs to see their condition. Any other suggestions?

filmy540i/6
08-16-2008, 06:00 PM
I wouldn't automatically go "head gasket". Depending on the seasonal humidity where you live, a certain amount of water will condense inside your exhaust when it cools off, and that water will steam out as the exhaust heats back up.

The other symptoms of the steam stopping once the engine is warmed up (heat expansion could be closing a worn surface gasket) and the reservoir level dropping may or may not be HG related.

I would say that if the steam smells sweet then it is probably a coolant leak into the exhaust - and probably the HG.

Paul in NZ
08-16-2008, 08:05 PM
this is normal,it takes much much longer than a few minutes for these exhasts to completley warm up...I would day 10-15 minutes before they drive the water out.If it is cold they will steam for that long.There are also local mini climates(Ussually where a valley intersects with the valley you are driving in) inter where the car will steam when it wasnt a few minutes before.

Ross
08-17-2008, 08:17 AM
Like thas been said it could just be weather conditions but combined with coolant loss you could have trouble.
The plugs will tell the tale. Coolant in the cylinder will effectively steam clean that particular combustion chamber. If one plug is conspicuously cleaner than the others it is a pretty good indication of coolant entering that cylinder.

Tiger
08-17-2008, 09:45 AM
I used to have this problem. It turns out to be that the spark plug is not firing at full power. Number of reasons for this...

1. Oil in spark plug hole that reached up into the coil boot.

and

2. Spark plug coil boot is shot.

The steam is result of your cats burning off the miniscule raw fuel. I replaced the coil boot and no more problem. The new design is much better... completely seals off the spark plug.

Mendozart
08-25-2008, 09:09 PM
So, I got around to removing the spark plugs today and looking through the spark plug hole I could see some water sitting on top of one of the cylinders:( More than likely my head is cracked. So, who here has succesfully removed and installed a head on a non-vanos m50 engine? Where did you get the special tools needed? Luckily my e28 is up and running, so I can take my time on this project.

Paul in NZ
08-25-2008, 09:13 PM
So, I got around to removing the spark plugs today and looking through the spark plug hole I could see some water sitting on top of one of the cylinders:( More than likely my head is cracked. So, who here has succesfully removed and installed a head on a non-vanos m50 engine? Where did you get the special tools needed? Luckily my e28 is up and running, so I can take my time on this project.

sorry to hear that...good luck!

Ross
08-26-2008, 05:51 AM
So, I got around to removing the spark plugs today and looking through the spark plug hole I could see some water sitting on top of one of the cylinders:( More than likely my head is cracked. So, who here has succesfully removed and installed a head on a non-vanos m50 engine? Where did you get the special tools needed? Luckily my e28 is up and running, so I can take my time on this project.


Water or coolant? water is just condensation or rain water, either of which could cause a misfire and unburned fuel going out the exhaust.
Dry it out and see how things are.

Ferret
08-26-2008, 06:44 AM
Water or coolant? water is just condensation or rain water, either of which could cause a misfire and unburned fuel going out the exhaust.
Dry it out and see how things are.

Yeah pull your fuel pump relay and kick her over on the starter for 60 seconds with no plugs in to vent the contents of the cylenders out. Put a soft, clean rag into the spark plug hole to collect the ejecta and have a good sniff see what it is.

If there's a lot of stuff in there, there's a good chance you've got a head crack. Purely out of interest is it cylender 3 or 4 that's full of water or another cylender?

I have a conspiracy theory going about the torquing method cracking the head as the head usually cracks around the first bolt hole.
A la:
http://i11.photobucket.com/albums/a190/Ferret101/Car/IMG_6159-1.jpg

You may however be lucky, so long as you pull her off the road immediately - she's not been overheating has she? This could be something as simple as an injector stuck wide open - how's your fuel economy?

EDIT: Pulling the head on an M50 isnt exactly a walk in the park, but it's not hard either. The special tools you need are basically a set of torx drivers and sockets, with a *very* narrow T8 (I think ) to remove one of the recessed bolts at the front of the head. You'll also need a straight edged steel rule to time her up if you cant be bothered/dont want to hire the official cam timing tools. Other than that it's all straightforwards run-of-the-mill tools

EDIT2: I forgot to mention the tie-wraps to hold the timing chain to the sprocket - a cheats method for not having to take the complete timing chain off :D

Mendozart
08-26-2008, 01:43 PM
Water or coolant? water is just condensation or rain water, either of which could cause a misfire and unburned fuel going out the exhaust.
Dry it out and see how things are.
It's definitely coolant.