Coolant Leak--no Idea Where It Is Coming From! - BMW Forum

moetinger · 05-24-2005, 09:09 AM

Right behind the drivers side front tire (closer to the driver-not closer to the front of the car) my car is leaking antifreeze and it is looks like it is coming out of the chassis. Does anybody know what hoses could be up there?

Thanks!

Mad_Milo · 05-24-2005, 09:58 AM

There is an assortment of hoses on the back side of the engine.

There are 2 going in/out of the heater core on the firewall, maybe a snarl of hoses from the early 80's bypass recall, and some hoses going to/from the intake and throttle body.

Get your car up to temp with the coolant full, shut it down, and pop the hood. Use your eyes, ears and nose and you should be able to trace them around. Give the hoses a squeeze near the clamped ends and in the middle, and you may find/hear some bubbling or hissing.

Go to RealOEM and enter your info, and then find the cooling system schematic for a list of standard hoses and approximate locations. It doesn't have the bypass on the older cars though.

nukeduster · 05-24-2005, 11:02 AM

the spot you described is the pressure overflow outlet. its for if you over-fill your coolant tank, it dumps out the excess coolant right behind the drivers front wheel. there is a hose that feeds down through there that lets it leak out onto the ground there.

you DONT fill the coolant system all the way to the top. otherwise, the situation you are describing happens, and everytime you check yoru coolant you will be like "WTF? wheres my coolant going?" well, its overfilled, so its getting forced out.

its normal, dont worry about it.

moetinger · 05-24-2005, 11:09 AM

That would make sense b/c I had no choice but to drive my car another 45 minutes and the temp needle didn't budge. I would think if the car was low on coolant, it would over heat pretty quickly.

thanks for the help!

Mad_Milo · 05-24-2005, 11:51 AM

That's assuming that the overflow is on that side. You never spec'd what car model or year you are driving.

My expansion tank and overflow is on the passenger side.

moetinger · 05-24-2005, 11:54 AM

1990 325 ic. The expansion tank is on the drivers side. About how full should it stay and should I be concerned that this is the first instance this has happened?

Thanks

Mad_Milo · 05-24-2005, 11:57 AM

Fill it to the full line on the tank when cold. That should give you a good reference mark.

offabroadway · 05-24-2005, 01:31 PM

The garage I've been to a few times has added coolant for me once when my coolant light went off, they filled it with the engine running and hot to the full mark, and then some of it dissapeared. It's kept a pretty steady level since then, but I always wondered why the coolant was leaving.

Glad I checked in on this thread.

Redbullrr · 02-27-2006, 03:49 PM

I just started a thread regarding an issue like this. The car is not overheating. I do have heat in the car and I was sitting put for about 15 minutes waiting for someone, and when I took off I noticed a small pool of antifreeze this was when I shut the car off then turned it back on. It wasnt still leaking, but when I checked my rad overflow tank I still had fluid but about 3 inches high. When I looked underneath the car it was as if a water gun with antifreeze went off down there. It was over my rim, and axles. Could this be what is going on?

Starmavin · 02-27-2006, 06:21 PM

Drivers side or passenger side. What year is your car?

Redbullrr · 03-01-2006, 10:30 AM

96 318IS. Its from the drivers side.

Starmavin · 03-02-2006, 05:41 PM

Is it still doing it?

fretsgonebad · 03-07-2006, 12:54 PM

I changed my coolant the other day and when i started up my car and let it run for a bit coolant started dripping like crazy out of this area on my car, too. It really freaked the crap out of me because i have never leaked coolant before. I drive a 1990 325i sedan. Is this the problem?