Why I installed a low temp thermostat.

[ChrisZang]

Originally Posted by MileHighBoxster

What you say makes sense and I have no reason to doubt that cooler is better. That said, the eminent engineers at Porsche seem to know what they've been doing for over 50 years.

Usually I would agree with that statement.
But please remember ours was the first water cooled flat 6 they ever built ....

[blue2000s]

Originally Posted by ChrisZang

Usually I would agree with that statement.
But please remember ours was the first water cooled flat 6 they ever built ....

But far from the first water cooled Porsche.

[MileHighBoxster]

Originally Posted by ChrisZang

Usually I would agree with that statement.
But please remember ours was the first water cooled flat 6 they ever built ....

15 years ago and, to my knowledge, not only have the original late 90's done fine - but they haven't felt a need to change it. Again, as I've stated above, I agree that a cooler running engine is probably better but I don't see any proof that the temperatures are detrimental to the engine. Additionally, as stated above, the thermostat operates on temperature not on the digital readout.

[nnewell]

The thermostat failed to open on my 190SL one summer day and I didn't see the
temp. guage climbing - in a few minutes the rad cap blew and so did the head gasket. A costly repair including a head rebuild later I installed a failsafe thermostat - 72c . These thermostats fail open. I used that thermostat for six years and never had another problem.

[MileHighBoxster]

Originally Posted by nnewell

The thermostat failed to open on my 190SL one summer day and I didn't see the
temp. guage climbing - in a few minutes the rad cap blew and so did the head gasket. A costly repair including a head rebuild later I installed a failsafe thermostat - 72c . These thermostats fail open. I used that thermostat for six years and never had another problem.

All thermostats, Chevy, Ford, Ferrari, Porsche.... can fail to open. It just doesn't happen very often.

[san rensho]

Originally Posted by MileHighBoxster

15 years ago and, to my knowledge, not only have the original late 90's done fine - but they haven't felt a need to change it. Again, as I've stated above, I agree that a cooler running engine is probably better but I don't see any proof that the temperatures are detrimental to the engine. Additionally, as stated above, the thermostat operates on temperature not on the digital readout.

For what its worth, other modern P cars, the GT2 and GT3s, IIRC, have 160 deg thermostats.

[Topless]

Yep, at 94K miles my original water pump began to weep a bit and since it is a known weak link, it had to go. While we were in there a new motorsport 160F T-stat and a few idler pulleys were replaced. 90% of this job is getting the car in the air, accessing the work area and draining and refilling the coolant. I do tend to use ALL of the car so a fresh 160F T-Stat at 94k was a no-brainer.

Would I have gone to the trouble of changing a working T-Stat if my car was only 4 years old, had 20K miles, and the water pump and coolant looked great? Nope.

[san rensho]

Originally Posted by Topless

Yep, at 94K miles my original water pump began to weep a bit and since it is a known weak link, it had to go. While we were in there a new motorsport 160F T-stat and a few idler pulleys were replaced. 90% of this job is getting the car in the air, accessing the work area and draining and refilling the coolant. I do tend to use ALL of the car so a fresh 160F T-Stat at 94k was a no-brainer.

Would I have gone to the trouble of changing a working T-Stat if my car was only 4 years old, had 20K miles, and the water pump and coolant looked great? Nope.

Replacing the t-stat was a piece of cake. Just clamp off the hose to the t-stat, take the hose off the housing, about 2 quarts of coolant comes out. Remove 4 bolts from the housing and its off. Reverse to install.

[Topless]

Originally Posted by san rensho

Replacing the t-stat was a piece of cake. Just clamp off the hose to the t-stat, take the hose off the housing, about 2 quarts of coolant comes out. Remove 4 bolts from the housing and its off. Reverse to install.

So did you change out that POS water pump while you were in there?

[san rensho]

Originally Posted by Topless

So did you change out that POS water pump while you were in there?

Did that last summer.

[mikesz]

I changed my thermostat to a low temp version when I changed out the water pump and replaced system with fresh coolant. I also added an S center radiator to my 99 base 2.5. Because I felt like it!