Hi all, I am having an issue with coolant leaking. The coolant only leaks once the car has been running for 15+ plus minutes. The leak occurs when I turn the car off and park it. I thought it might be the old blue radiator cap so I changed that to the new black model and still nothing. The coolant drops down onto my left muffler bypass and seems to be coming somewhere above the panels that would sit above the factory muffler. Any ideas?

 

The bleeder valve on the coolant expansion tank may be the culprit. I believe there may be an o-ring that requires replacement. Just a guess. But, I would start there. Good luck.

 

I recently had a coolant leak and where it was where a larger hose met a machined part about a foot or so right of the center of the engine. It's a bit hard to explain exactly, but i saw a corroded seal on the hose. I think the machined part was defective. They told me that that part has been redesigned twice. Mine had a seal that had been placed on top of another seal. I dunno if this helps..

 

Prob the coolant tank itself.

They are notorious to split.

 

brando is right, 9 times outa 10 its the tank, grab a mirror and flashlight and look along the bottom and rear of the tank, look for a buildup of chalky pink residue and possible wetness, itll be just a small crack letting out a small amount of fluid

 

It's most likely the tank towards the left wheel well that cracked. You won't see the crack until you remove the tank.
The updated tank has a "03" part number at the end and has reinforcements in that area.

 

Gonna try and take a look at the bottom of the tank today. Thanks eveyrone for the help.

 

My coolant tank kept slightly leaking for months. Never saw a drop hit the ground but I kept adding it than after about 4 months I saw it dripping out of the drivers side tailpipe. I touched it and it was oily, opened the engine lid and sure enough it was way low.

Thank God I bought a warranty, it cost me $100 deductible at the dealer to get replaced.

 

definantly the coolant tank. i had the same exact problem, when i took the car to my mechanic we lifted it up and looked underneath. it was very difficult to tell where the leak was coming from, even after pressure test. he diagnosed it to be the coolant tank. once we changed it the leak stopped.

 

I'm experiencing the same problem with my '99 911, small drip running off left side exhaust, I also noticed coolant around the overflow tank cap. I'm starting with the new cap first, Dealership in North Eastern Ohio quoted about 750.00 for new overflow tank. I purchased the cap for 20 bucks on the web. If this isn't the caper, would one amateur be able to replace the tank or is it a really intense repair? Any help is appreciated.

 

I bought the cap first, coolant kept disappearing for months and then the leak that looked like it was coming out of the exhaust pipe...the tank developed a leak. Get it checked out ASAP.

 

Just noticed coolant residue on the left exhaust, sure enough the tank is leaking, not much but but the level is low.
Has anyone replaced on your own?
It doesn't look terribly difficult unless it gets more difficult as you get into it?
Any do it yourselfers out there?
02 992 C2

 

Check the DIY section, I think someone has posted a great article (you can check rennlist forums as well... perhaps I saw it there). You do have to lower the engine a couple of inches, but it honestly isn't abig deal. However, that resevoir is shoe-horned in there like a motherf*!&er ! The key is to be PATIENT. Also, I hear it's a great idea to buy and extra level sensor (like $20), as it is on the bottom of the resevoir and there are people that have broken them when tring to install the new resevoir. Good luck and don't be affraid to tackle.

 

Done, New Coolant tank installed.
Had to lower the engine as far as it would go with out additional force, probably 3" or more.
A real pain getting the old one out, but the new went in easier than I thought
I took my time and guessing a total of 6 hours over 3 days.
Thanks for the word of encouragement and tips.
J