engine temps in Southern Cal?

[MNBoxster]

Originally Posted by CJ_Boxster

I live in socal and did clean my radiators already, I usually run anywhere from 90 celcius to 103 on a hot day. I could be needing a radiator flush and maybe need to use more water than antifreeze maybe 20/80.

Hi,

How can you say that? These are just estimates because the needle will be in-between the hash marks.

The minimum mix you want with your coolant is 50/50. Any lower, and you're reducing the lubricating and anti-corrosive qualities of the mix which will have consequences down the road. Your Boxster isn't any different than anyone else's, if you're running Hot, you need to identify and eliminate the cause, not try to compensate for it. Besides, there's nothing wrong with 103°C, at this temp, and at pressure, the coolant is still a liquid (below boiling point) and providing maximum cooling...

Happy Motoring!... Jim'99

[Brucelee]

Actually, I find an oil temp guage to be much more informative than the coolant temp.

The Covette C5 and 6 has one and it is not a fake out, ie it reads temps by degree and changes pretty quickly.

Using that I have found that the oil temp will usually run about 10 degrees hotter than the coolant, UNLESS you are flogging it. In that case, the oil can get REALLY hot.

If i were tracking my Porsche in the CA heat, I would be running Red Line oil or M1 15W-50, both of which are more shear resistent than the M1 0W-40 oil.

Also, if I were doing a lot of tracking, I would likely get larger oil coolers.

[MNBoxster]

Originally Posted by Brucelee

Actually, I find an oil temp guage to be much more informative than the coolant temp.

The Covette C5 and 6 has one and it is not a fake out, ie it reads temps by degree and changes pretty quickly.

Using that I have found that the oil temp will usually run about 10 degrees hotter than the coolant, UNLESS you are flogging it. In that case, the oil can get REALLY hot.

If i were tracking my Porsche in the CA heat, I would be running Red Line oil or M1 15W-50, both of which are more shear resistent than the M1 0W-40 oil.

Also, if I were doing a lot of tracking, I would likely get larger oil coolers.

Hi,

Excellent points. Your Oil is actually responsible for carrying away 60% of the heat produced by the engine, while the Coolant removes 35% and Airflow around the motor accounts for the other 5%. And, while the Coolant flows around the engine, it's the Oil which removes the more critical heat from the Journals, Big-Ends, and such where the Coolant does not flow. This surprises most people.

And don't forget the importance the Sparkplugs play in managing heat by carrying heat out of the Combustion Chamber to the Head where it is extracted by both the Coolant and the Oil flowing through it...

Happy Motoring!... Jim'99

[CJ_Boxster]

Interesting, well i can say that cause i wasnt estimating those numbers i gave, I used my AC controls to tell me the coolent temps... So 103 is fine???? weird cause i remember in a previous convos on this forum you were telling me that my car running at 93 celcius was too high. Ill find that convo....Heres the quote from you in the past

"That said, 216°F is a little on the high side (not fatally, but high) for normal conditions. Make sure both your fans are working (turn on AC) and that both radiators are free of debris (a common problem). No two cars are exactly the same, so some variation is normal."

With that said, your beginning to give me one answer and then another in later days.

Originally Posted by MNBoxster

Hi,

How can you say that? These are just estimates because the needle will be in-between the hash marks.

The minimum mix you want with your coolant is 50/50. Any lower, and you're reducing the lubricating and anti-corrosive qualities of the mix which will have consequences down the road. Your Boxster isn't any different than anyone else's, if you're running Hot, you need to identify and eliminate the cause, not try to compensate for it. Besides, there's nothing wrong with 103°C, at this temp, and at pressure, the coolant is still a liquid (below boiling point) and providing maximum cooling...

Happy Motoring!... Jim'99

[CJ_Boxster]

Do the radiator fans in the front of the car turn on when the car reaches a certain temp or do they only turn on when the AC is turned on?

[subgraphic]

My needle stays on the 8 in the 180° mark, no matter how hard I drive...

[CJ_Boxster]

Originally Posted by subgraphic

My needle stays on the 8 in the 180° mark, no matter how hard I drive...

Do you ever hear your radiator fans infront of your car turn on while your AC is off?


I called the Porsche Service and they told me that they are suppose to click on in the 180 range...estimation*** and also if the AC is turned on, They said it im reaching the 190 to 200 range without them turnin on, then he said something is wrong... They also said that the fans have 2 stages... regular and high...I guess they will spin faster if the car continues to get hotter.

[MNBoxster]

Originally Posted by CJ_Boxster

Do the radiator fans in the front of the car turn on when the car reaches a certain temp or do they only turn on when the AC is turned on?

Hi,

The Radiator Cooling Fans have two different speeds and are controlled by the DME. The operation of the Fans, or the selection of the Fan speed, is not temperature dependent alone. The DME uses several other variables to determine the Fans operation.

These include: Ambient Temperature (determined by Intake temperature from the integral Temperature Sensor in the MAF), Driving Speed (from the Wheel Speed Sensors, to judge the airflow through the radiators - another reason why keeping the Radiators clean is important), Engine Speed (to judge the vol./time of the Coolant flow - Coolant Pump flow is rpm dependent), Immobilization time since "Ignition OFF" (to judge heat buildup), AC Refrigerant Pressure (from the AC Pressure Switch, to judge load placed on Engine, affecting Engine Speed, especially at idle).

So, you cannot judge the proper operation of the Fans by the Temperature Gauge alone. In one instance, at one displayed temperature, the Fans may operate, or may operate on either High or Low. In another instance, with the same temperature displayed, the Fans may not operate at all, or may operate at a different speed.

For example, at idle, say at a Stoplight, the Fans may operate on High speed at Coolant Temperature X, while at 65MPH, at that same Coolant Temperature X, the Fans may operate at Low speed, or may not operate at all. There is a Temperature Default in the DME software which will override the other variables given the following conditions:

The Fans will always work on Low speed: When the AC is switched ON, or if the Coolant Temperature exceeds 96.75°C (206.2°F).

The Fans will always work on High speed: If the Coolant Temperature exceeds 102°C (215.6°F), or the AC Pressure Switch is CLOSED (when Refrigerant Pressure exceeds 16 bar or 232 PSI).

The caveat here is that the Fans may indeed work in the Default Mode, but due to a failed or failing Switch or Sensor, may not work optimally under normal driving conditions. This may account for some of the varying operating Coolant Temperatures some owners report having, but there are so many variables involved, that it's impossible to say for sure.

Hope this helps...

Happy Motoring!... Jim'99

[CJ_Boxster]

Originally Posted by MNBoxster

Hi,



The Fans will always work on Low speed: When the AC is switched ON, or if the Coolant Temperature exceeds 96.75°C (206.2°F).



Hope this helps...

Happy Motoring!... Jim'99

THanks, this is the peice of information i was looking for, When i get home Ill let my car idle for awhile until it reaches 96.75 cel and see if they turn on at all. Cause i dont ever recall them turning on at all UNLESS i turn the AC on. Thanks Jim

[MNBoxster]

Originally Posted by CJ_Boxster

THanks, this is the peice of information i was looking for, When i get home Ill let my car idle for awhile until it reaches 96.75 cel and see if they turn on at all. Cause i dont ever recall them turning on at all UNLESS i turn the AC on. Thanks Jim

Hi,

Be sure to read my ammended post, because even though the Fans come ON in the Default Mode, doesn't mean that they are necessarily operating properly outside the Default parameters. The only 2 things which the Default Mode really tells you is that the DME is recognizing the Default parameters, and the Fan Motors work. Hope this helps...

Happy Motoring!... Jim'99

[CJ_Boxster]

Originally Posted by MNBoxster

Hi,

Be sure to read my ammended post, because just because the Fans come ON in the Default Mode, doesn't mean that they are necessarily operating properly outside the Default parameters. The only 2 things which the Default Mode really tells you is that the DME is recognizing the Default parameters, and the Fan Motors work. Hope this helps...

Happy Motoring!... Jim'99

Ok, got it, Im just worried weather not they are turning ON at all when the AC isnt on...cause sometimes i know i get really high temps in slow traffic on hot days but all i hear is the engine fan turn on. but never the radiator fans, I just would like to see if they trigger Low Speed at least when the temps reach over 96-97 celceius at a stand still...