How hot is too hot?
05-04-2017, 10:59 AM
#16
Rennlist Member
The 180+ on your temperature guage looks normal to me. It's common in the water cooled engines to go to 230 or even higher during hard track use and Porsche says the 0W-40 is fine. And no, the 0W and 5W are related to low temperature viscosity and won't help at high temps. Going from the 40 to the 50 might be appropriate for very high ambient temperatures, such as in exceptionally hot places like the desert or the Middle East countries. Some people do that viscosity increase for high mileage engines, and for those with higher oil consumption.
Last edited by PCA1983; 05-04-2017 at 11:16 AM.
05-04-2017, 11:10 AM
#17
Three Wheelin'
Thread Starter
Car has 73k miles. Coolant was replaced in 2013 at 60k miles by previous owner when he did the waterpump, new tank and low temp thermostat. Rads are clean. I checked them when I removed the front bumper last month to have it resprayed.
05-04-2017, 11:14 AM
#18
Rennlist Member
On my 2000 C4, the gauge warms up to the left half of the zero in 180, and slowly moves to the right side of the zero when in stop-go traffic. On the move, it settles in on the middle to left half of the zero on 180. All fans seem to come on when they are supposed to and the heat never gets higher than the right side of the zero.
The same was true for my 2000 black cabriolet prior to sale as well. Temp needle behaved pretty much the same before and after I put in a 160 degree t-stat.
From the sounds of it, your car is behaving normally.
The same was true for my 2000 black cabriolet prior to sale as well. Temp needle behaved pretty much the same before and after I put in a 160 degree t-stat.
From the sounds of it, your car is behaving normally.
05-04-2017, 11:20 AM
#19
Shameful Thread Killer
Rennlist Member
Rennlist Member
Porsche and a few other mfg put the temp sensor at the exit of the heat source(engine). Most other, and I think all Japanese cars put the temp sensor at the exit of the thermostat area. Since the exit of the thermostat regulates the temp, if you see any large changes at this point on the car, it's cause for concern. On a Porsche(at least all the water cooled ones I've had), you will see the unregulated temp of the engine, even though it is not the hottest point of the cooling jacket. Therefore, you will see more swings in the temp gauge as the engine(heat source) works harder.
To validate this, in any other car when first starting out, note the temp gauge indication as the car is driven. As the engine warms, the temp gauge will go up to the setpoint, and maybe just slightly higher when the thermostat isn't open. Then, there will be a rapid but short decline as the thermostat opens and the cooler water flows in from the rad, followed by normal regulation. This doesn't happen in the Porsches I've owned.
To validate this, in any other car when first starting out, note the temp gauge indication as the car is driven. As the engine warms, the temp gauge will go up to the setpoint, and maybe just slightly higher when the thermostat isn't open. Then, there will be a rapid but short decline as the thermostat opens and the cooler water flows in from the rad, followed by normal regulation. This doesn't happen in the Porsches I've owned.
05-04-2017, 01:00 PM
#20
Rennlist Member
If you read some other threads on this issue the first problem is that the coolant sensor is not at the hottest part of the coolant circulation system. Then there is the accuracy of the gauge. If you can resolve those 2 deficiencies we can discuss specific numbers with some confidence we are all talking about the same thing. Otherwise it becomes difficult to progress beyond anecdotes. The Track guys have this all resolved because a mistake could mean an engine rebuild. They may be a better source of accurate info because they may have calibrated the stock gauge against more accurate instruments with better sensor locations?
For what it's worth, mine runs about 188 degrees on freeway, then spiked as high as 210 when slowing in bad traffic.
05-04-2017, 01:29 PM
#21
Rennlist Member
On my 2000 C4, the gauge warms up to the left half of the zero in 180, and slowly moves to the right side of the zero when in stop-go traffic. On the move, it settles in on the middle to left half of the zero on 180. All fans seem to come on when they are supposed to and the heat never gets higher than the right side of the zero.
The same was true for my 2000 black cabriolet prior to sale as well. Temp needle behaved pretty much the same before and after I put in a 160 degree t-stat.
From the sounds of it, your car is behaving normally.
The same was true for my 2000 black cabriolet prior to sale as well. Temp needle behaved pretty much the same before and after I put in a 160 degree t-stat.
From the sounds of it, your car is behaving normally.