So I assume the red letter box is the new genuine Porsche water pump? Yes there are OEM manufacturers that are not genuine Porsche which can be confusing. Another example is Pieburg...something like that anyway

I remember catching some chatter on another forum indicating that Lasos fail early

Thanks Jager for clarifying on the brand of the waterpump that failed so rapidly. While we will never know whether the Porsche part would have lasted longer or not, I am certainly planning on replacing mine with the factory part when the time comes. And yes, I have decided that I will not replace the pump until there are signs of failure, in spite of the urgings of some others.

In the interim, I am careful not to open the coolant expansion tank when the engine is warm as per Pedro's advice. When I replaced my serpentine belt this spring, I checked out the pump for signs of leakage or play in the pulley and all seemed good. There is also no discernible bearing noise when it is running. I also decided not to replace the lifetime coolant as, it strikes me that if there is a problem with the bleed, I am more apt to cause an impeller failure than if I leave well enough alone. When (or perhaps if considering Pedro's waterpump life) I need to replace the pump, then I will have the system flushed and the coolant replaced. I am also holding off on replacing the thermostat with a 160 degree unit for the same reason. Until then, I am leaving well enough alone.

It might be interesting to see if those who suffered early pump failure had previously had the system flushed and coolant replaced, or had required replacement of the coolant expansion tank, or had replaced the thermostat, or had been opening the coolant expansion tank when the engine was hot. Furthermore, if the system had previously been bled, what method was used.

Brad

Just got hold of my new pump.

I find the drag on the pump bearing quite high. You can hear as you spin it and it does not spin for very long maybe two revs before it stops.

Is this normal?

The LASO I put in failed within 30K miles. It blew apart. I replaced it with a factory part. There were clear differences in machining quality. I also used the Airlift tool and after filling have never had to do any extra bleeding. Fast and precise, I would recommend nothing else.

failed laso:

http://986forum.com/forums/uploads01...1368662205.jpg
http://986forum.com/forums/uploads01/wp21368662243.jpg

comparison:
http://986forum.com/forums/uploads01/wp31368662414.jpg

I now have the bleed valve open for a couple days... Do I close it hot or cold? Do I remove the reservoir cap to burp the system again while it is hot (per the Bentley manual) before closing the bleed valve?

Wow! Didn't the pump make some noise before blowing-apart?

Jager, for my two cents I would not open the reservoir while it is hot. Before I bought my uvIew Airlift 550000 for the vacuum bleed I did several flushes using just distilled water. Anytime I tried to open the reservoir there was venting. Even with the purge valve open. I'd recommend letting it cool. Doesn't have to be completely cool, but can't be at operating temperature.

If you are in Southern CA, you are welcome to stop by and use my vacuum system. After my first fill, and running the motor, I let it cool down and created a vacuum again and added another 1/2 gallon using the system. Since then it has been running at normal temps. I seriously recommend buying a vacuum system for the coolant flush or water pump replacement as it works very well and eliminates the need to bleed the system.

Thanks Paul... Me too.

Thanks... I will run it for a couple days, wait for it to cool-down, then close the valve.
Thanks for the offer... I think I am in Southern CA? But they call this the "Central Coast", I'm in Santa Barbara county.

What sort of noises and symptoms indicate the pump failing.

Reason I ask is because I hear a bit of a rattle when idling that I think is new and my guess would be the pump bearings or the timing chains.

It even does it when hot so thats probably less likely the timing chains?

Would I see coolant loss over time if its the pump bearings?

My car has ~65K miles on it and still on the 1st pump I think.

Anyone have comments on this?

Jager,

That would be quite a drive to Palm Desert, CA. But if you need it let me know and I'll mail it to you.

Take a look at my thread describing my symptoms prior to the failure. Maybe that will help ...

http://986forum.com/forums/general-discussions/45036-example-how-water-pump-failed.html

The pump has a lot of drag. Even the new one I installed will not spin for long. But it should feel smooth with no side to side interaction/drag. Mine was off center and was slowly scoring the top bolt. You could see it when the engine shield was removed.

jaykay - I'm pretty sure the OEM pump had a bit of drag but was smooth and tight. It did not spin much at all after you let go. As long as you don't hear any scraping or irregular sounds you should be good.

As far as sounds when mine blew up, I had my head under the car earlier that day or the day before and heard nothing too strange. While driving I heard an intermittent squeak/squeal/chirp that I attributed to the Ferrari 308 in front of me. I'm not sure if that was me or not but but 10 or so miles later there was steam coming out the back and at low speeds it sounded like a bag of rocks being shuffled around.

And as far as leaking, the coolant tank had not lost any fluid in nearly 2 years. So it was not dripping any coolant before it failed either.

-Greg

Thanks for the info! The pump I have has the part number 996 106 101 where as others have 996 106 011 56. Is one an older version?

My original pump started having grinding noise (at ~202,000 miles) and then started to leak a little, leaving a spot on the garage floor, and I replaced it with a LASO. The LASO pump starting to fail (after 40,000 miles) did not leak but is started to make noise that I can best describe as one of those old crank sirens (not as loud) being turned at a slower speed and increasing pitch as the RPMs increased.

Most of the advice about refilling the system is based on doing it quickly and getting the car on it's way.

If you have the time.....

I've had excellent results with just filling the system with the vent open then starting the motor with the cap loose and adding coolant as it warms up to keep the tank full. Once the level stabilizes, I bring the tank up to the full line and close the cap and vent and let the car idle until the radiator fans run. Then I let it cool over night. In the morning if the tank is not completely empty, I just top it off and it's good to go.

If it's empty, I repeat the process.