Why I installed a low temp thermostat.

[san rensho]

Originally Posted by ultimate1

I have to check with Pelican today but I think the wahler stat comes with housing for $70

Yes it does.

[ultimate1]

Is there any difference in quality between the Wahler and LN Engineering low temp stat? I have LN ims upgrade and love their product but saving $100 is always worth trying to do if it makes sense.

[Flavor 987S]

How much additional (if any) time would an indy shop charge for this upgrade while doing a coolant flush and serpt belt change? Thanks.

[san rensho]

Originally Posted by Flavor 987S

How much additional (if any) time would an indy shop charge for this upgrade while doing a coolant flush and serpt belt change? Thanks.

Four bolts to change it out. 1/2 hour max.

[Jaxonalden]

Originally Posted by ultimate1

Is there any difference in quality between the Wahler and LN Engineering low temp stat? I have LN ims upgrade and love their product but saving $100 is always worth trying to do if it makes sense.

Read the info on both products;

Porsche Boxster Cooling System Miscellaneous - Page 1

They both have the same description, "German-made 160F thermostat pre-installed in a new, OE Wahler thermostat housing and gasket." The LN is $100 more...sounds like a no brainer to me.

[Flavor 987S]

Originally Posted by san rensho

Four bolts to change it out. 1/2 hour max.

Thank you. that's kinda what I thought (and was hoping to hear), since they "are already in there".

[Bala]

I just installed the Wahler replacing the original. They look similar and the Wahler seems of good quality. It took me maybe 25 minutes. That's because one bolt is hard to access and I did not have a swivel type ratchet. You will have to drain some coolant - about 1 gallon.

[bar10dah]

I'm fast approaching 75K miles. A mileage where some say is a good time to change out the water pump as preventive maintenance.

I'm leaning towards the 160F Wahler. How difficult is it to use the specialized tool to replace the thermostat into the original cover? Is it worth the trouble to save a few bucks? Seems to be only about $6. Or just get the thermostat/cover already put together?

UPDATE: Disregard. I was looking at the wrong listing. Appears fro Pelican, $70 for all three pieces; thermostat, cover, gasket. $69.50 for just the thermostat insert...

[kotto]

Originally Posted by bar10dah

I'm fast approaching 75K miles. A mileage where some say is a good time to change out the water pump as preventive maintenance.

I'm leaning towards the 160F Wahler. How difficult is it to use the specialized tool to replace the cleaning thermostat into the original cover? Is it worth the trouble to save a few bucks? Seems to be only about $6. Or just get the thermostat/cover already put together?

UPDATE: Disregard. I was looking at the wrong listing. Appears fro Pelican, $70 for all three pieces; thermostat, cover, gasket. $69.50 for just the thermostat insert...

Where did you see the listing? I myself am looking at grabbing a thermostat to somehow increase something with my car. Anyway, I think it would be best if the dealers are to install it for you.

[tranceatlantic]

I installed the LN low temp thermostat a few weeks ago. I noticed that the temp gauge seem to sit at the lower temperature for a while but then eventually moves back up to its previous normal temperature position (needle approx vertical on a 1999 986). I figured this was because once the thermostat is wide open the final running temperature will be dependent on the radiator design/size etc.

One word of warning though. If you do a coolant flush don't park your car on an inclined driveway with the back end point down the hill. The air vent for the system is at the rear but the radiator is at the front. I had an air bubble in my radiator, went auto-crossing and blew my boiled coolant all over the place. For those of you without PhDs in physics; air goes up.

[Bala]

Originally Posted by bar10dah

I'm fast approaching 75K miles. A mileage where some say is a good time to change out the water pump as preventive maintenance.

I'm leaning towards the 160F Wahler. How difficult is it to use the specialized tool to replace the thermostat into the original cover? Is it worth the trouble to save a few bucks? Seems to be only about $6. Or just get the thermostat/cover already put together?

UPDATE: Disregard. I was looking at the wrong listing. Appears fro Pelican, $70 for all three pieces; thermostat, cover, gasket. $69.50 for just the thermostat insert...

I installed the Wahler bought from Pelican. Absolutely no difference in engine temp between stock and the low temp one. Installation was a pretty simple tho.

[coolbreeze551]

Originally Posted by Bala

I installed the Wahler bought from Pelican. Absolutely no difference in engine temp between stock and the low temp one. Installation was a pretty simple tho.

I found the same thing ... What is up with that?

[Chuck W.]

Originally Posted by Bala

I installed the Wahler bought from Pelican. Absolutely no difference in engine temp between stock and the low temp one. Installation was a pretty simple tho.

Originally Posted by coolbreeze551

I found the same thing ... What is up with that?

Can someone answer this? TIA.

[Jaak]

It seems the T-stat opens earlier to get the coolant flowing earlier, that's all it does.

Nothing else changes with the temp as the car still generates the same amount of heat as before. The temp gague is slow to change unlike the ones the 944's have and show's an average over a short time span. My old 951 used to move up and down all the time ...

[Meir]

The key to the question has to do with the somewhat strange cooling system in these engines. I'm sure someone can explain it better then me, but as far as I understand, the temp sensor is located at the return from the rediators (I think you can fined the full explanation in earlier posts in this tread). There are parts of the engine (around cylinder 6 if I remember correctly) that are much hotter than what you see on the gage. So even thogh the gage show same readings, the engine itself runs much cooler.
That's more or less what I understood before I got main

[thom4782]

Someone said it earlier: the thermostat trigger point only effects when the radiators begin to affect the temperature of the circulating coolant.

If the thermostat is closed, the coolant temperature of the coolant rises because the heat input from the engine is far greater than the loss. Essentially engine generated heat is lost directly from the engine block into the surrounding air. This is a very inefficient heat exchange.

Once the thermostat opens, the rate of heat loss in the coolant increases because the radiator exposes a large surface area of hot coolant directly to the lower temperature of the surrounding outside air. The rate of heat loss increases even further when air flows over the radiator as the car moves forward and refreshes the air surrounding the radiator with cooler air. This is why cars have radiator fans which increase the rate of heat loss when stopped in traffic.

It may be in boxster engines that the balance point between heat in from the engine and heat out from the radiators is above 160. If this is the case, then the low temperature thermostat has little effect on lowering the temperature gauge reading. If it does have an effect on the gauge reading, you would most likely notice it on cold winter days when the heat loss from the radiators is much greater because of the temperature difference between the coolant and outside air is much greater than on summer days.

I experienced this personally in college one frigid winter day as I drove my MGC from Connecticut to Ohio. The temperature gauge read Cold for the first couple of hours until the outside temperature warmed up to 20F. Then the gauge started to move about 1/3 up the scale toward Hot. There was some heat in the car from the heater. Late that day when the sunset and the outside temperature fell below 0F, the gauge fell back to Cold and I froze when the heater only blew cold air.

So the main reason cars have thermostats IMHO is to make sure the engines get up to an efficient operating temperature regardless of how cold it is outside and to make sure the heater warms the inside of the car. The radiators and the fans keep the coolant temperature from getting too high so the engine suffers less heat fatigue and doesn't allow the coolant to vaporize in the worst case. BTW: the coolant can remain a liquid at temperatures above the boiling point of water mainly because the coolant system is pressurized.

[Nimbus117]

I'm not convinced. It takes oil twice as long (as a guide) to get to temperature than the cooling system so I keep my revs low until then anyway. The only advantage I see is that the heater will warm the interior quicker in winter - except the car spends the cold months in the garage.

[kjc2050]

I installed a Wahler 160* thermostat this weekend (in addition to replacing the water pump and changing the coolant). The coolant is now at ~82*C when fully warmed up and the car is driven a moderate speeds. Prior to this change, the coolant was at ~88*C under the same conditions. Yeah, I know I changed the coolant in addition to switching to a low temp tstat; this was hardly a scientific experiment. But there's little doubt that the engine is running a bit (~10*F) cooler, and I doubt the coolant is responsible.

BTW, used the AirLift to fill the system. What a great product!!!! Took about 90 seconds to get the system to 25 lbs. vacuum; about 3-4 minutes to fill the system, and that included adding more coolant mix to the 5 gal bucket I was using. Worth every penny +++++.

[pothole]

Originally Posted by Chuck W.

Can someone answer this? TIA.

I think people are looking at buffered gauges that won't show any changes unless they are very dramatic.

You need to be looking at the temp via either the aircon screen hack or better still via the OBD port.

The lower temp stat will make a difference to the normal operating temp as when the car is cruising at speed, it's the stat that determines the operating temp, if you had no stat at all the capacity of the rads to cool would lower the temps quite a bit at a constant cruise at say 60mph.

What I'm not clear on is why the stat would help keep things cool when the car is under heavy load etc. Once the stock stat is fully open (which happens at a much lower temp than when the car is heavily stressed in any case), there's no difference between the two stats. They are both just open.

And as far as I can tell, the reason to have the low temp stat is not reduce the temps at a constant cruise. It's to stop the coolant getting really, really hot. And it's not going to do that as both stats are full open long before the temps get really hot.

[JFP in PA]

Originally Posted by pothole

And as far as I can tell, the reason to have the low temp stat is not reduce the temps at a constant cruise. It's to stop the coolant getting really, really hot. And it's not going to do that as both stats are full open long before the temps get really hot.

The stat set the minimum or baseline coolant temperature the car is going to run at and return to when cooling off from a higher temp like when stuck in traffic. Because the stat consistently lowers the baseline temp of the coolant, it also lowers the oil temps as well, which is even more important.

As for why people don't see much movement in the dash gauge when using one, that is simply due to the grossly inaccurate and non linear nature of factory gauge, which is little more than an idiot light with a pointer.