Weird coolant leak observation
 

Looks like coolant is leaking from somewhere on the driver's side of the car. The leaked coolant is finding its way down onto the bottom pan undre the car (near engine oil filter and plug) and evetually leaking to the ground from one of the holes on the pan. I looked from all angles (from under and over the engine) to try to find out where the leak is coming from, but it's impossible without removing many engine parts. I know it's coming from the back of the engine on the driver's side.

Here's the weird part: If I park the car on an incline with the nose up, the leak is quite substantial. It leaks much less on a flat surface. However, if I part the car with the nose down, it doesn't leak one bit!

Any one experienced something like this? Any thoughts? Thanks.

Weep hole big money! Go with the All German pipe it will save you $2000+.

Isn't the weep hole on the front of the engine. Therefore, it would leak if the nose is pointing downward on a slope. My car only leaks when the nose is pointing upwards.

Check all the hoses dude, I had a pinhole in one of mine and it leaked so much I thought it was a serious matter, but it was only the little hose that runs along the top of the radiator harness... Had such a little hole man but it was leakin like crazy everywhere! Good luck

What year and how many miles.

2005 with 98K miles

Hmmm, hard to tell where water originates based on the drip. Weep hole is common at this mileage. Of course check all hoses- would be well worth having an indy check it out if you can't locate it which will be very hard without a lift or dye.

If it is the dreaded weep hole, as mentioned the American made All German product is an excellent alternative ($1,600 installed at All German in SoCal vs $9,000 to have the dealer tear the engine apart and repair with the same defective design).

Hoses are a breeze relatively speaking, hope it is that.

Thanks... but as I mentioned earlier, the weep hole is at the front of the engine; and if it was indeed the weep hole, I would've seen the coolant coming out of there. Also, the leak would be greater when the nose of the car is pointing downward. In my case, when the nose is pointing downward, there's no leak. It only leaks when the nose is pointing upward.

While that is very logical and hopeful, the system is pressurized and may leak any way it wants to unrelated to gravity or position. The olnly way to know for sure is to look. Assuming hoses are clear, Methinks you should do a search here to find the procedure to check the weep hole. I think it is visible to the naked eye.

The weep hole is dry. I was hoping someone had a similar experience that would save me the trouble of having to take it somewhere to get it checked out.

I had a similar leak but it may be different for you since I have the V12. My leak was at the back of the motor above the transmission bell housing. It was either the lower intake manifold gasket or the valley pan gasket. Either way, it cost my warranty company 3K to fix b/c of all the parts removal on the V12. The gasket itself wasn't that expensive. It was less than 100 dollars if I remember correctly.

Water Pump? The rubber gasket might be worn down.

I second to that! definitely check all hoses as long as your a little mechanically inclined remove all top plastics you'll get a better view! i had a little leak & it was a little Y plastic piece that was like $45-$60 from dealer!

I recently had a leak ,and it was coming from the sensor located on the lower water hose which has an O Ring that wears out after a period of time , check it out just to make sure .

Here's the thread

http://www.bimmerfest.com/forums/sho...t=#post6454571

Several places to look:

1. Vent hoses (small) on the inner part of each head, just below and to the left and right of the throttle body / intake manifold opening...these meet and go to a single hose that runs to the coolant reservoir. Mine were leaking where they were clamped to the heads.
2. Metal coolant pipe running from back of water pump meets a rubber hose at the back of the intake manifold (either the hose, or a bad metal pipe-to-rubber hose connection).
3. Numerous coolant hoses coming out of firewall (from/to heater core) behind intake manifold.
4. Valley pan gasket (thin rubber gasket that goes around metal plate that covers coolant feed pipe)...a leak from here also means that the O-ring at the front of the coolant feed pipe is going bad and water will - or should be - coming out of the weep hole.

got to this link it you want to know the story behind the leak. I hope this helps someone.

http://www.bimmerfest.com/forums/sho...571&highlight=