Tracking down coolant leak - 2000 B5 S4
 

I'm working on my S4 tonight. Over the weekend I had the clutch replaced with an RS4 clutch, pressure-plate and AWE flywheel. Since then and while we were working on it, it sprang (sprung, did spring?) a coolant leak from somewhere - we're not sure where, just coolant all over and running down the stationary part of the bell housing (not sure what the exact name would be, but it's the bell-housing that stays on when you have the tranny removed - coolant is running down that from the front of the car and dribbling off the bottom of that stationary bell housing.)

Current thinking is that it's the auxiliary water pump since that's a common failure point for this car, so I'm going to pick one of those up along with all the O-rings and seals I need for that piece and associated stuff and crossing my fingers that that will be it - we're going to pressure test the coolant system, BUT I'm checking all available options, so if anyone has any other advice or suspicions I would appreciate the feedback.

I'd also like to hear any worst-case scenarios people might have so I can start to think about that if we strike-out tonight. My worst-case scenario is that during this some coolant got in and fouled up the brand new clutch/flywheel?...how likely is that?

(excerpts cross-posted on various local (MN) discussion boards)

Thanks!!!

Bif

Could be the rear main seal gasket...

A. Gonzalez?

lol

"take me off the distribution!!"

Your off.

That would be in the 'worst case scenario' category?
 

I can't find this in alldata (no surprise, but...) is this known by another name? What other assy. is this connected to/near?

Thanks for the info!

s/b under Toasty's reply - sorry.

So your saying there was never a coolant leak before installing the new clutch..
 

I havent figured out where my leak is from. Possible diagnoses i have come up with are Aux Pump, and/or Temp sensor to pump, Grab a flash light and look between your intake manifold at Aux pump, if there is pink liquid there than thats most likely the culprit. This is an e-mail i have received and not my own research

"ok the only time an aux pump would create an INTERNAL coolant leak is IF and ONLY IF the coolant gets passed the top cover gasket and gets into the engine .. VERY VERY unlikely imho. that thing is sealed up tight . so forget that imo .. good to check but that is not the problem."

You could have a cracked head if you have oil and coolant mixed together. The thing with my car is that i have done numerous searchs and have found no leaks. Nothing driping from the bottom of the car. It's like my car is eating up coolant every week. I have not replaced any parts, as there are no signs of bad parts. I will be doing an oil analysis, and pressure test. If i find nothing i will be putting Bars leaks in my coolant tank and see if that does anything. I will let you know how everything goes. If there is anything i missed or have givin false information please correct me as i am not always right.

Not that I could see or notice...
 

...but inside the bell housing (in the empty space around the flywheel/clutch area) was some dried up stuff that a more experience individual identified as long-dried coolant. We've since determined that the leak must be in the valley there so I'm assuming it's just been leading up to this and we shocked the motor enough putting the tranny back on that something broke all the way?...I'll know more tonight.

Your quoted-email is comforting...in a way :)

Many thanks for the thoughtful reply, I'll report back what I find here. Thanks again!!!