The most likely failure in my 2001 Box base...

[oc-boxster]

It was the first thing I did when I bought mine. My 02 had 80,000 miles, and there was no proof it had ever been changed so I had to assume it was original to the car. It wasn't making any noise or running hot, but I went ahead and replaced it anyway along with a low temp thermostat.

[san rensho]

General wisdom is to replace the water pump preemptively every 4 years or 50k miles or so. If the pump goes, the plastic vanes can crack off and clog the coolant passages leading to localized overheating and a cracked head.

[Dlirium]

Originally Posted by san rensho

General wisdom is to replace the water pump preemptively every 4 years or 50k miles or so. If the pump goes, the plastic vanes can crack off and clog the coolant passages leading to localized overheating and a cracked head.

^ That. Replace it. the downside is HUGE, and the cost is minimal.

And just FYI, for those of you that don't know - if your battery light comes on, turn off your engine IMMEDIATELY! Chances are, your waterpump shaft broke and the belt fell off. You are literally 2 minutes from a baked engine...