E46Fanatics - View Single Post - Help with unidentified coolant leak, [pics included]
View Single Post
Old 11-17-2012, 02:38 PM   #1
Registered User
Join Date: Jul 2010
Location: MA
Posts: 517
My Ride: BMW 323i
Help with unidentified coolant leak, [pics included]

Hey guys, I have a coolant leak going on that almost got the best of my car. I was sitting in traffic, then without warning, the low coolant light came on. The engine temp stayed normal though, so I figured maybe the level was just a little low. Sitting at a red light, eyes on the temp needle like a hawk, I saw it start to creep up. I started to get nervous and pulled off to the side of the road when it was safe to, it was in the red zone for probably 30 seconds. I pulled over in a parking lot, opened the hood:

-No smoke anywhere, slight smell of coolant but not strong at all (supports my theory that it all leaked out onto the road)
- Completely EMPTY expansion tank, bone dry, some steam coming from that when the cap was off
- When I put bottled water into the ET, it emptied out onto the pavement at the same rate that I was putting it in up top. It was also pouring rain out, and I had no tools with me, so I couldn't get under there and see what the issue was, but I concluded that the ET exploded.

All of this resulted in this:

The next day, I got under the car with some tools, but couldn't see anything moist or wet, all looked normal, all hoses attached and such. I poured more bottled water into the ET, and this is what I saw:

That fluid is rippling down that black hose device there, not leaking right from that, and that is DIRECTLY beneath the expansion tank.

So today I take out my expansion tank... BIGGEST PITA in the world, this thing would NOT come out. After an hour of wrestling with it, I got it out, but not without breaking the bleed screw valve I know Mango would clap for me for saying I'm going to replace the ET regardless, but now I have no choice. Also, I'm looking at my ET in the sink under a light, and I can't see any noticeable stress fractures or holes or anything.

Anybody have part number or names for the bleeder screw that connects to the bottom of the ET?

If it wasn't my ET that blew up, what could have been the reason coolant just spilled out so quick?
bostonsc4 is offline   Reply With Quote
Ads by Google

Guests, get your FREE E46Fanatics.com membership to remove this ad.