What I gain from this thread is don't change the WP until it tells you to.

 

Hmmm... interesting.

 

Here is the reasoning as I've gathered from prior forum posts: Occasionally the failure of our water pumps is not a typical bearing, seal, or shaft failure with the resulting noise and/or leaks. The bigger problem occurs when the non-metal impeller blades disintegrate and chunks of the blades get caught in the engine's coolant channels and restrict coolant flow along some of these channels. That is typically why people here consider a proactive change.

 

Okay, I just noticed the other water pump thread going on in parallel and have to say that Ericson38 describes this much better than me. See his post at https://rennlist.com/forums/997-foru...uestion.html#8

 

Since I am considering a higher mileage (58301) 07 C4 Targa I have started lurking on this board. The threads are interesting, but if I was to make a slightly uninformed comment about the failures being talked about can changing the water pump as preventive maintenance I would ask if the failure is just part of mechanical wear and who is to say the replacement would fail after installation from just bad luck on my part?

 

Anyone ever seen the plastic impeller comes loose with their own eyes? Or is it just you hear about it?

 

Last week my 2005 997 carrera water pump start leaking, at 97k it seems this is not unusual. I collected the car yesterday after they replaced the pump. My problem is I can see from the part number they have gone an fitted a 996 mk2 water pump, part no 99610601157.
Car now drives fine, water temp and oil temp sitting in the same place it used to, no leaking.
I've read the impeller size was changed by 2mm, and even the material may have been changed from plastic / metal / ceramic.....do I need to go back to the garage and insist they change it or do you think I'm ok and leave it as is. It seems the 996 mk2 is interchangeable with the 997 mk1 WP....but have I just downgraded and if so does it actually matter? Car is used daily for road work only. Thanks!

 

I had to replace the water pump on my 2008 C2S this summer with only 25K miles. No collateral damage. Fidelity covered it with a $100 deductible.

 

AFAIK, stock Audi pumps are like Porsche, composite. If yours was metal, could it be that someone replaced it? Those composite pumps are a weak spot on the Audi too. Everyone changes them to metal and replaces them on every belt service (I do too).

 

With your context in mind and in the pursuit of insight for others, how long have you owned the car and what, if any, has your approach been to lengthen the life of that system - have you changed out the coolant regularly, do you have a third radiator, are you a track junkie, etc??

 

Original owner, maintenance is always way ahead of miles and driven by time. Those things that are not on a maintenance clock, like water pump, I do on a preventative timeline based on my Indy's advise and/or a trend in occurrences in other people's 997.1's. Just recently did a Numeric Shifter and cables based on the trend that our Shifter cables break in the 60k range and I'm at 58k....so upgrade. I did the FF orange inserts for fun and I left them in for a couple of months but the NVH was too much for me. I still get a little with the Numeric cables but it is a nice sound to me.

Light tracking, no 3rd radiator as I never have seen the oil temp over 230F at the track with 95F ambient, but coolant was has been changed 3 times, the last time being with the water pump. At 60k I'll do another major (I do every 20k), and this time the coil packs will be changed as well and maybe the AOS. Still running the original clutch and RMS as well.

Does this help extend the life? Perhaps, but I have never had a CEL and the car always gets me home....waste of money, could be, but the next owner will benefit as it will most likely be my son.

 

I don't think it was necessary to just go out and replace a perfectly good water pump. You could have removed the serpentine belt and rotated the pulley to get a feel for it. Wiggled it a bit and visually check for leaks or signs of leaks. Water pumps typically give you visual or audible indications before they go out. I understand your concerns and maybe you had good personal reasons for doing this but for the most part, this was pretty foolish.

 

I'm in agreement with this for water pumps. I pull the airbox and serp. belt to check all the pulley bearings. If something spins quickly by hand or sounds dry it get's replaced. Means the original bearing grease is gone and the bearing will begin to wear much faster. Also check for torsional and lateral runout. Any play and I replace.