I just replaced a 20 year old waterpump...
 

I finally got around to my waterpump, low temp thermostat and coolant service after 5 years of ownership . The pump which was original was absolutely perfect- spinning freely and all of the vanes were just like new. I should’ve taken a picture of the old and new side by side- they were hard to tell apart. Granted, my car has only 42,000 miles on it, but I can’t help but challenge the belief that the pump can time out before it miles out.

This is the first waterpump that I have ever changed - it was a fiddley but not particularly difficult job.

Good feedback. I have 41K miles on mine and will not worry about water pump

Congrats on the install! You saved some serious quid doing your own labor? What are you going to spend it on?? ;)

Ciao, I believe that Porsche recommends replacing the water pump at 40k, it's actually not too expensive

I replaced mine at 92K, once I noticed a tiny bit of play in the pulley when I changed the serp belt. I'm sure it wasn't done before because the gasket was not cut. The vanes were all intact, as well.

I’m glad I did mine - but seriously 40k! Why should that be necessary? We had a Honda that went to its grave with the original pump at 335,000 Kms. The car was still going strong with only normal maintenance, but met it’s demise after an encounter with a light pole.
Is Porsche using poor quality parts, or is the pump unusually stressed compared to “normal” cars?

The only other vehicle that I have ever had to do a water pump in 30 years of vehicle ownership was a GMC Acadia (the last GM that I will ever own). The pump went at 40,000 miles- I thought at the time that was pathetic.

@pilut2...

I swapped mine out a couple of years ago and you’re right about the water pump and thermostat being a fiddly but relatively easy DIY.
Good on you not spending hundreds on labor.
These cars really aren’t that difficult to work on and maintain.

Why did you go to a low temp thermostat??
What temp thermostat did you go to????

I've got a little over 40,000 miles myself so this makes me feel a lot better about my waterpump.

And yeah congrats on doing it yourself....Before I bought mine(My first Porsche)I had doubts about the IMSB thing and working on a mid engine car but after being on this forum and reading about people doing their own work on these cars makes me realize I made the right decision to buy my little roadster.

I went with the 160 degree thermostat after plenty of research on this forum and elsewhere.

A month ago I had my 20 year old (1998) water pump replaced due to a slow but persistent leak that wasn't getting any better. One week after that, I had to replace my 20 year old coolant holding tank in the rear trunk. It was leaking from "spider cracks" on the underside of the tank that weren't visible. As the cooling system would come up to temperature and pressurize the "spider cracks" would weep coolant and that liquid would accumulate under the rear trunks raised flooring. Eventually the coolant would find its way to the garage floor a few drops at a time........but that too would only get worse, so I had the tank replaced too. Since I'm not a DIY person I paid for the work.......all in for both I spent about $1,900. Not cheap but since the car hasn't needed repairs for the last 15 years I consider I got off easy.

Well, that’s timely information. My 18 year old tank is beginning to do the same thing I believe. I haven’t taken a real close look but I am getting some drops occasionally on the garage floor. After years of reading what a pain it is to replace the tank, I may take it in to have my Indy do it along with a new water pump, time for that too.

Hmmmmm. I have the new waterpump and low temp thermostat already at home. I'm planning to change those in a couple of weeks.
Now this coolant reservoir tank is getting me worried since the car is 2001 model 986.

If the coolant tank is leaking in to the trunk, is there a best place to look for the leak from the trunk - where the coolant would find it self if there is a small leak?

Check under the carpet/liner in the trunk near the tank for wetness.
Replacing the tank with an original Porsche part is recommended. Aftermarket tanks have often proved to be unreliable; you don't want to do the job twice!
DIY tips and videos abound. You might want to tackle this job, it's not as daunting as many make you believe! :)

I am still curious as to why people go to a lower temp. thermostat when they change the water pump.????
Are they tracking the car???

Search this forum or google it. There is a ton written on the subject. The goal is to help your engine to run cooler.

The system is designed to run within a certain temperature range.
Are you saying you go to a lower temp thermostat to stay within that range??
Or do you go to the lower temp thermostat to run the engine cooler then that range?????

I did a WP a few years back on by 2000S at 122K miles when I noticed a slight leak from the area. When I removed the carpet and panel to exposed the front of the motor, I started the car and could see a slight mist coming from the WP. During the removal, I noticed that one of the WP bolts in the area of the leak was loose. Given the the torque spec is 7 lb-ft, I wasn't sure if that was the issue or not, and given I had a new OEM pump and thermostat (and that this was the original WP) I when ahead with the replacement. Inspection of the original pump after removal showed a pump with no play in the bearing and the impeller looked like new.
Most likely was a loose fastener. Oh well.

Ok- so you don't want to do the research.... I'm not an expert, but those who are explain that the stock thermostat starts opening at about 186 F and is fully open by 210 F- whereas the low temp version starts opening at 160 F and is fully open by about 185 F. This results in lower operating temperatures- oil and coolant- for more most driving conditions.

I'm no expert, either.

Yes, with the lower temp thermo it opens at a lower temp... but it keeps getting hotter until it reaches operating temperature. The low temp thermo does not cause the engine to run cooler.

So "This results in lower operating temperatures" is incorrect.

I installed the low temp thermo and my operating temps have remained unchanged.

Please DON'T RELY on seeing or feeling a "wet carpet" in the truck in order to determine IF the coolant tank is leaking! In my case the carpet was bone dry and the tank was still leaking (actually weeping from it's bottom when up to temp and pressurized).

The trunk in my 1998 has a masonite type of raised flooring that sits 1 inch above and between the metal trunk floor and the carpet....that allowed the coolant to collect below the masonite raised floor and just slosh around until it eventually found a way to drip a few drops on my garage floor.

I suggest you removed ALL the fabric lining in the rear trunk (bottom & sides)....(easy to do but time consuming). Then lift up the raised floor boards and drive the car for a day or two and just keep opening the truck to look for coolant collecting. I took rolled up paper towel and placed it all around the tanks sides and bottom, drove the car for a bit, and saw the paper towel began getting wet.

I have done research, lots of it over the years.
It is why I am surprised that so many people are going to a thermostat that is outside the manufactures system operating parameters.
When you run cooler then the system is set up for it takes longer to go into closed loop.
You run on cold startup fuel map longer.
harder on the Cats. hard on o2 sensors
Running at lower temp takes longer for the oil to reach its operating temp. (which is typically very close to 195)
Resulting in oil being bypassed at the bypass valve for a longer period of time.
Takes longer for the oil to reach a temp where it burns off water.
For every pound of fuel burned (that's about half a quart) a pound of water is produced. Not all of it goes out the tail pipe.
Some of it ends up in the oil.
Just a few things that result from running cooler then spec.
Now if it is a race car or a car you track I get it.
If it is a street car?????

So that is why I was curious as to why it seems that lots of people are going to the cooler thermostat.

Makes sense; factory specd water pump has and continues to be my choice.

I recently had my cooling system overhauled, and originally wanted to get the lower temperature thermostat, but was persuaded by several shops not to for the same reasons blue62 mentioned.

My car is 99% daily driver, and there is a 1% chance I'm going to the track regularly (once a year at most, and if even.) If my Boxster were a dedicated track/race car, I would have opted for the lower temperature thermostat. It gets quite cold in Toronto over the fall and winter months, so the last thing I need is for the car to warm up to operating temperatures longer than usual. I'm also not attempting to break world records on my 35KM commute to and from the office every day. Most of the time, I'm stuck in stop and go traffic.

My experience has been different than yours. I drove for a hour or so yesterday with a combination of city and highway driving. In stop and go traffic my temps (according to the gauge) were slightly lower than with the stock thermostat but my highway temps showed a significant reduction with the needle settling just under the 180 mark, where it would've previously been a few needle widths higher, resting in the middle of the 8. It is my understanding that the actual coolant temperature is a fair bit higher than the indicated temperature- so there is no concern about the temperature being too low to burn off any moisture in the oil.

Pilut2... interesting.

There seems to be two camps on the efficacy of the low temp thermo.

I'll wait for Jeff in PA to chime in. I'll follow his recommendation. If that means he recommends the stock thermo... I'll soon be swapping my low temp out.

Cheers!:cheers:

Some great back and forth in this thread.

http://986forum.com/forums/boxster-general-discussions/33593-why-i-installed-low-temp-thermostat-2.html

Simple: It is better for the oil, and for the engine. In spite of your research, the only reason the factory run these cars so hot was emissions, period. Back when LN first introduced a 160F thermostat, we collected data on UOA's in cars before and after installing the thermostat. Net result was that nearly all of the oil values (film strength, TBN, viscosity, water content, fuel content) were excellent for longer run times on the car running the cooler thermostat. We saw absolutely NO increase in either fuel of water contamination in oil samples, and oil quality was much better for many more miles. We have also seen no change in O2 sensor life or performance, or in cat life expectancy. And contrary to your data, oil temps in these engines are typically much hotter than 195F when running the OEM stat; 225-235 is more like it.

As for fluid warm up, your data is also suspect. How fast an M96 heats up is a function of the engine's specific heat out put rate at any given ambient temperature; the thermostat functions just like the one in your home: Regardless of where it is set, how fast the temperature rises is constant, only the point at where the thermostat takes control and throttles the system changes. Fully instrumented M96's warm up both the oil and coolant at the same rates, regardless of which thermostat is in play. Only their final "steady state" temperature changes.

You might also be interested in the fact that every turbo, GT2, and GT3 car left the factory with a 160F stat in them...…….

JFP
Glad to see you jumped in on this.
Yes it seems all car manufactures number one concern is emissions everything else being secondary.
The primary reason modern day cars run hotter then pre smog days.

Interesting data you collected.
Good information to be considered.
Always trying to broaden my knowledge base.
I wonder if your findings are relatable to most modern day cars???
That would be interesting information;)

Thank you, Jeff.

You saved me some quid, and peace of mind. Coffee on me next time you're in SoCal.

Or a cocktail. You can choose your poison.

:cheers:

This is the same behavior I'm experiencing with the low temp thermo. You see a more detailed temp readout looking through the ECU.

I now feel stupid and regret getting the factory thermostat after reading JPF in PA's reply. lol :(

Don’t feel stupid. You sought advice, but just got it from the wrong folks.

Thank you Rob175 and NewArt for this very good info. I'm back from travels and will open up the carpets on the wekend to come. I've had the car only 2 months and can see now that the water in the reservoir is at the lower mark now when the car warm... can't remember how it was at the time of purchase :eek:

From what I've seen, the DIY job of replacing the tank is VERY difficult unless you can raise the car and work underneath in addition to from the top. Remember there is also the connections for the oil dip stick and oil filler in addition to coolant connection. For me, I didn't want to tackle the job because failure or any difficulties encountered in the process would render the car un-drivable......and the cost to have it towed in would exceed the price of my "indy" doing the job AND guaranteeing the work. But, having said that, there are some that do tackle it, just not me.

Good luck and keep us posted.

That's one DIY I would probably have the Indy do; there are many others that will save me $ equalizing the cost of having the tank done by the Indy.