Engine overheating

Just finished rebuilding my 1978 SC 911 3.0 L engine. Installed it and everything is fine except that the engine starts to overheat over a shrot period of time.

Checked the timing - set ok although I havn't checked the advancment at 6000 rpm's. The fan shroud is sealed properly, the belt is tight. Have good air flow from under the engine. Temperature continues to climb at idle or higher rpm. Checked the pressures on the fuel system its ok and adjusted the airflow/fuel mixture both lean and rich - no change.

The engine probably takes a good half hour or longer to hear up. While investigating, I did notice that the oil going to the oil cooler under the right front fender does not get warm until the engine temperature indicator is just below the red zone on the gauge. I did notice that when I am driving, the temperature falls a little, not much - still over to the 3/4 way mark. It is possible that this could be causing the problem? Any suggestions.

Get a new oil temperature sender - they aren't too expensive. It sounds like that's the problem, especially if it doesn't "feel" like the engine is hot yet it registers hot on the gauge. That's what I'd bet on.

Good idea to get a new sender for the oil temp gauge. Just make sure it is the right one....I would first check to see how hot the oil is getting. Buy or borrow a pyrometer it is a hand held evice that can tell you at a glnce the actual temp of your oil when pulled out on the dip stick.

Racer Supply in GA, has them...

Check the thermostat in front of the right rear wheel. If you determine, through a pyrometer, that your oil is above 220 degrees or so, but your front oil cooler is cool, then the thermostat is not working properly.

Thanks for the info. I think the problem might be the temp sensor for the oil cooler. The oil gets pretty darn hot before the line to the cooler starts to warm up. The oil in the tank did reach over 220 before the oil cooler got warm. Again, appreciate the info.

Thanks for the info. I think the problem might be the thermostat for the oil cooler. The oil gets pretty darn hot before the line to the cooler starts to warm up. The oil in the tank did reach over 220 before the oil cooler got warm. Again, appreciate the info.