Coolant leak? but from where?

[Kmoy2002]

This morning, I went to my car and I noticed a puddle of coolant under my car. I I took a look underneath the car and I noticed this:



What could this be? I changed the radiator, got new hoses, re-torqued the cylinder head, but i still get this leak.. what could be the problem?

[Andrew Elmore]

Mines doing the exact same thing.

It started happening after i changed out my water pump and replace my oil pump. Ive got that same slow leak that wasn't there and i dont see any leakage around the water pump.

Hopefully we can get that leak tracked down, its annoying leaving puddles everywhere lol

[Mless5]

I once had a problem on my now gone 535is: lower hose that comes to the radiator that is on the left if you're facing the carn had a really bad clamp that I was unaware of. I developed a slight leak and while driving, the fuild would get blown of by the wind right to the area that is pictured. Might be worth looking at.

[spinedocab]

Freeze plug, maybe. They can rust through and weep. How much is it losing how fast??

[Kmoy2002]

It seems to be a very slow leak. It only leaks if i drive the car hard. But if i take it easy and go on nice, easy drives, then the leak doesn't leak coolant.

[papajetta]

i'd get a pressure tester, ( maybe 30 bucks ).
its really good for those situations where it only leaks sometimes.

[alotawatts]

I'm still learning to speak E28 but E12's can often leak were the coolant lines connect to the bottom of the throttle body. Helps warm things up I think. Often corrosion is the problem.
I hear in mild climates you can just bypass this circuit of the cooling system.
Your leak looks like the other side though ...maybe not ?

[Tjn182]

A leak in that spot makes me think of a few things:
1) Headgasket - take a look in your oil and anti-freeze and make sure they aren't mixing. The oil will be chocolate milky brown if it's contaminated, and the anti-freeze will have blobs or layers of oil film.

2) Loose hose - Check the upper and lower radiator hoses

3) Water pump seal -- could have gone kaput

that is where I would start! Good luck.


[Edit by Tjn182 on [TIME]1133795072[/TIME]]

[Kmoy2002]

Thanks guys for all this help. I recently put in a new cylinder head gasket in so that cat be the problem, but i'll check the seal on the water pump or the hoses.

[Marinersfan]

I had coolant leaking that I couldn't trace and I finally found it coming from the tranny bell housing. It was misdiagnosed as a freeze plug leaking that was behind the flywheel but that person thought I had a 2.5. If you DO have a 2.5 that may be your problem. Mine on my 2.7 turned out to be the head gasket. Replaced that and no more leaks. But if your like me and have a 2.7 there are NO freeze plugs on the rear of the block. If it is a freeze plug somewere else is should be easy to spot. Another place it COULD be is the hose from the heater valve to where it bolts to the rear of the block. A real PIA to get to. I ended up dropping the motor. One other place that I had a problem leaking was a coolant flange to the intake manifold. It's square and located right next to where the intake boot connects to the intake.

[a]

I wonder if the the onset of cold weather has something to do with it. Ive had to tighten several hose clamps on various things through out my fleet lately. Also , when I changed water pumps along with the timing belts on Swarz and the Borman6, I noticed that the hose nipples around the thermostat housing were pitted from corrosion. I used some Permatex brush on goop to help seal them. I have noticed a small puddle under the Borman6 lately after I shut it off after my 50 mile drive to work. It looks to be a failing seal on the right tank of the radiator. So far , its about a tbs per shut down.