water pump
 

My box is 10+ years old an I have never changed the water pump. What are the dangers of this....?

According to Jake Raby (Flat 6 Innovations), the highest risk is the plastic impellers breaking and lodging in the cooling passages in the cylinder head. Not so much mileage, but age can make the plastic brittle; I would venture you are on borrowed time. My 3.2 is going to be 9 years old this spring with only 19k miles on the clock...I plan to replace the pump just as a precaution.

Great more plastic parts..........agreed the thing needs to come out. Had no clue the impeller was plastic

I've been thinking of changing mine for the same reason. 12+ years old with 127k miles. NAPA has a reman for $144 or new for $158. Has anybody used one of these from NAPA ?

Why cant we get a metal impeller replacement ?

I'd double check that "new" price. I sell a reman for $160.00 and the new pump is $358.00.

just changed mine, got it new for around $200

go to sonnen porsche, while your down there i recommend changing to the low temp thermo from LN

Get a genuine Porsche water pump. Why would you risk your engine and go with a remanufactured pump?
I'm all for saving money but some things are worth spending the extra for the genuine article.

Does the replacement water pump have non-plastic impellers? Or are we just replacing one pump for another pump with the same plastic impellers? So, if we bought a Porsche OEM pump, what are we gaining?

i think most feel the plastic is superior than the metal in this case, as the metal will expand and cause leaking.

but it's possible i'm crazy and thinking of sonething else.

From a thread in October:

The future is plastics - well at least it was in 1967
 

Here is what a "lightly" used pump looks like.

okay...... that got my attention!

You are correct KPM, I did make a mistake on the price for the new water pump from Napa. Their web site says it is $154. I think my local store quoted me the $158.

So the question is still unanswered. Has anybody tried one of these from Napa ?

Will I be the first to do so ?

Also, Please help me understand the reason the 160 degrees thermostat is better than the 190. It is my understanding that an engine not up to at least 180 degrees does not opperate at peak efficiency. Give me a little more detailed information so I can give my car the best treatment too.

So, if I get the gist of this thread, we replace the water pump with a Porsche OEM pump (plastic) impeller (JTP) every 2-3 years (Jake).

Well, I guess I am due to replace mine (4 years). Who has the best price on a new OEM pump. My Boxster is a 2007. What do you think it will cost me to have the dealer replace it?

I know this has been said many times before, but also look at changing your front motor mount at the same time.

Yes......I keep hearing this and always wonder what the deal is. I suppose there is a huge polymer section to it and it is susceptable to embrittlment over time? I am at 11 years and have never felt anything like the engine shifting around. I guess I would have to be out of the car and maybe have a look. Is there a 997 upgraded mount that all are using? Is it fair to say that there is no additional labour in getting at the mount while you are at the pump? I would like to do these myself if they are feasible using jack stands....

987, not 997

I just had my water pump changed on my 01 box with 37k km.

The plastic impellers were still perfect, the pump seems in pretty good shape.

But at least now I've gotten rid of one potential problem...

Also had the low temp thermostat put in.... temperature is now usually slightly above 80 degrees C, goes up to approx 90 degrees when pushed hard (same as prev). No other noticeable difference though.

I changed the serpentine belt at the same time, although it still looked good. And was very glad I did, got rid of the whining noise especially when the weather is cooler or engine is cold..

I installed the Napa remanufactured pump just after Labor Day, when mine went bye-bye during a drive through the Rockies.

So far, so good.

Since its a lifetime warranty from Napa, I have more confidence in it, than something that came from some other type of shop that has part suppliers of less than stellar quality.

Plus, they also had the lowest core charge out of all the sources I looked at.

BC.

Change all water pumps after 3 years of service, despite mileage. After 3 years the heat, coolant and time in service have proven to create issues that cost engines.

If you drive your car 300 miles in 3 years, you still must change the pump to avoid the costly failures associated with the partial water pump failure that put 12 cars from 11 different states in my parking lot right now.

I'm sure Jake is right but
 

you can go broke changing/improving every little bit to decrease your probability of failures. Not to mention the added potential for problems caused by mechanics error.

It makes sense in F1 racing...but on my car?

Recall that Jake says there are 21-22 failure modes. Does it make economic sense for every M96 owner to go try and prevent them all?

Where do you start and stop? How do I know what is the risk of failure and how do I know what is the risk of spending to fix problems I won't have?

If I just look at Jake's 'cpo" list of fixes that starts to add up to some serious money and it improves your chances how much? And leaves how many potential failure modes? And how many yet undiscovered? After all the guy who had #21 could have had an engine with 20 fixes and it still failed.

How do you prove to yourself that just letting it fail and buying a used/"cpo"/new engine when/if it does isn't a better economic decision?

How many of the recommended fixes are said to have to be done again in some number of years/miles? IMSR/AOS/water-pump...what else?

I've spent thousands on cars over the years improving things that only got sold on to the next guy for no added money. Why not just take your chances?

I know that a lot of these questions don't have answers and I mean no disrespect to Jake when I use his name in asking them. Nor do I expect him to have answers. I doubt Porsche does. I only present the questions to cast some doubt that the answer is as black or white as some may make it out to be...it sure is gray to me.

+1 on that, Mike. When I first started reading the forum I had this list going - AOS, MAF, O2 sensors, water pump, clutch.....and on up to about 4 or 5 grand by the time I was done. Then I realized I was breaking one of my main rules - if it ain't broke, don't fix it. Decided I'll fix things when and if they break and I'll probably save a fortune - after all the car could get written off tomorrow and all that time and money would have been for naught. Chasing what might break can work out to be pretty expensive insurance.

I think there are a couple of exceptions to this: I buy into what Jake is saying about water pumps - results don't lie. I will also upgrade my IMS bearing, but only when I need to go in there anyway for an rms or clutch and, like most people, I'll do all three at that time. The gamble here is that the IMS won't be the first of the three to fail.

If I'm one of the unlucky ones that has one of those engine-destroying failures, that will be my excuse to replace it with some serious horsepower. It's an ill wind that blows no good!

And in another thread somewhere
 

Jake said there are several makers of OEM water pumps and one is better than the others.

So the decision making gets more complicated:

Ignore
Replace with NAPA rebuilt
Replace with NAPA new
Replace with any OEM
Replace with Jake's special OEM.

What he didn't say is which brand of oem pump is better, or why it's better. And, if you're going to replace it every three years anyway, how much better does it really need to be?

This water pump business is indeed rather complicated.

Water pump and t-stat replacement difficulty
 

Okay so let's assume we have the best replacement pump and t-stat. How problematic is this job? I would have to do it on ramps or jackstands