HenryPcar

I've read quite a few instances that the 997 water pump being plastic have a tendency to break. I'm sure given time its not a question of whether these plastic impeller will eventually break, but when. My 997.2 has 50K miles and wonder if I should change together with the thermostat for the next cooling service. Its a job quite capable of DIY with the necessary tools. Anybody has change the pump with metal impellers ?

bhvrdr

You want a plastic impeller pump. Id go with the pierburg. Totally up to you if you want to do it as "preventative." Youll get opinions on both sides.

mike

aaks38

I have 75k on an 07 4S and have a perfectly running water pump but am replacing it as preventative maintenance as i also needed to flush the coolant. The general rule is to use the plastic impeller as the oem one is this way.

mikemessi

It's my understanding that the 997.2 (9a1) pump is a different design than the 997.1 (M96/M97) and doesn't have the issues of impellar blades breaking and circulating through the system or eroding into the block. I think you can watch for the typical signs of water pump failure such as leaking coolant or noisy bearings/wobbling pulley before needing replacement like all other mass produced engines.

sandwedge

The water pump on my -09 C4S gave in at 43,000 miles. No warning. No coolant leak, no funny noises. Nothing. It just seized up and trashed the serpentine belt along with it. Total tab came to just shy of $2K if memory serves. FWIW....my service advisor said failures once the mileage reaches 40K is not uncommon.

mikemessi

OK. But no destroyed block secondary to impeller blades eroding into it or circulating through it. A seized bearing. Replaced for the same price as preventative maintenance basically.

mikemessi

Does everybody replace the water pump on their daily driver at 40k miles? It's a likely/possible failure after 4 to 6 years or 40 to 60k miles. Answer is no you wait until it fails because not everybody will experience it. A lot of things could fail. You wait until there are signs/symptoms in my opinion otherwise you are always fretting the "what if." I think at 60k you replace the serpentine belt and idler pulley and consider the water pump if there are signs.

KingPinLasVegas

I was worried about this exact same thing. I have some crystallization forming and thought it would be a great time to change the water pump. I'm buying a new Panamera Turbo for my wife so I happened to be at Gaudin Porsche here in Las Vegas and mentioned it to the service manager and he specifically told me DO NOT change it. He said that the crystallization is normal and changing it just to change it can lead to more issues. If it's not broken don't mess with it. Two other very reputable and very experienced shops here in Las Vegas told me the exact same thing. BTW...This is for my sons 2009 C4S Cab with 46,000 miles on it.

Petza914

PM change it between 45-60k miles. That way you do it on your time schedule and at your repair facility of choice, which could be your garage. If you wait for failure, you're at the mercy of when and where that happens and will surely cost you more and could have questionable workmanship.

Always use a plastic impeller pump. The problem with the metal impeller is if your pump fails due to bearing play, the tension from the belt and the play in the bearing can allow the impeller to mill into the block destroying the shape of the cavity and then even a new pump won't work very well.

They can fail with no warning. Wife's was fine, took the kids to school, came back, went to leave for lunch, and huge pink puddle under the car with no drips or noises previously. I keep a spare and a LTT in the parts cabinet just in case. Hers will be due again in about 10,000 miles, but I'm ready if it fails sooner.

BaileyII

jellonailer

I just did mine yesterday with low temp thermostat. PITA. My impellers were perfect at 63K miles, probably 4000 track miles.
Bearings were noisy on old pump but car was running hot. Car now runs 190 oil, 175 coolant.
See post below about my issues.

SoCal C2S

Tsilnner

A timely subject, as I was wondering about this issue after scheduling a second pump replacement on a BMW with 110K miles. My 09 S just hit 40K miles and I changed the coolant last year, so I'll wait. No track, original owner.
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However, what is the approximate cost (parts and labor) for installing a new pump and thermostat if the belt is not damaged?

Wayne Smith

Worth noting .1 vs .2 here. They are not the same thing.

I've exceeded 110K miles now and am on the original pump. In fact, original everything excluding tires (replaced three times in front, four in back), motor oil/ filter(replaced twenty some times), brake fluid (flushed twice and due), front rotors and pads (replaced once), spark plugs (replaced twice), PDK oil and pan (replaced once), and poly V belt (replaced once but the removed one was still in great shape).

That's a complete list and indicates consumables only. No hard component hassles.

IMHO the engineers at Porsche stepped up with the .2 design, throughout the entire car.

I suspect others with .2 cars will echo my experience.

In other words, the .2 with 9A1 motor does not appear to match the data of the previous generation. When talking maintenance, we really need to be careful to not mix these two very different designs together.

To the OP with .2 car ... I would not pre-emptively replace the water pump.

Edit add on ... 2010 C4S PDK. And I did replace a front axle boot due to chip seal damage that occurred in Idaho (buckets of rocks lodged into the undercarriage). I am not blaming the car for this!!!

BHMav8r

I would.

You will have to replace eventually anyway. cheap insurance/peace of mind. Do it on your terms or on the water pumps.

I was going to do mine (997.1) at around 60K, but my bet failed so I had my indi do it while they were there.

Agree that the .2 appears more reliable than the .1's