overheating problem

[ornas]

Hi, during this summer I have faced overheating problem on my 86 930 turbo. I am talking not about overheating in traffic jam in a daytime, but overheating at evening traffic at about 25-30c. Front cooler was warm, but not 100c or so and my car does not have a fan on the oil cooler. I have changed external thermostat, but it did not help. Can internal thermostat affect engine temperature in such way?

[86 911 Targa]

Originally Posted by ornas

Hi, during this summer I have faced overheating problem on my 86 930 turbo. I am talking not about overheating in traffic jam in a daytime, but overheating at evening traffic at about 25-30c. Front cooler was warm, but not 100c or so and my car does not have a fan on the oil cooler. I have changed external thermostat, but it did not help. Can internal thermostat affect engine temperature in such way?

Is this a new issue, or have you had the car for a long time?

Porsche did not add a fan until the late '86 production.

1. Upgrade to a fan with a 210F sensor.

[Joe Bob]

Fans are good for bumper to bumper traffic when there is no air flow over the fan.

Overheating in normal traffic is a thermostat issue.

[ornas]

Originally Posted by Joe Bob

Fans are good for bumper to bumper traffic when there is no air flow over the fan.

Overheating in normal traffic is a thermostat issue.

can internal thermostat affect in such way?

[Joe Bob]

They can. Verifying temps when the internal and external thermostats open are important.

Hand held IR Pyrometers are a good tool. Run the engine and watch your temp gauge. When you see it get to 180F verify the temps with the pyrometer.

Your gauge will have temps in Centigrade, they are very small and are on the extreme left side edge. You will have to put your head close to the clock and look in at the gauge. They are under the shadow of the bezel. Unless, of course you have a modded gauge with big numerals.

Once the t-stat opens the temp dips, then will go back up a bit as the external oil lines and cooler fill with warm oil and circulate in the oil tank.

If the t-stat opens over 190F, you might consider replacing it.