Over heating 66 Dart

The original engine for this car was a 225 slant 6. It never ran hot. The 225 had began to use oil and it needed to be rebuilt. I had another 66 Dart GT with this 273 4bbl engine. That one was wrecked. I took all the V-8 stuff out and put the engine in the current 66. The 273 4bbl in the original body did have some overheating issues when it sat at idle for a long time, but the radiator in that one was leaking and destroyed in the wreck. This car has all the V-8 brackets motor mounts and so forth to put this engine in this car with no aftermarket parts. The only things I have changed from the original 4bbl engine is the 302 heads, new aluminum radiator, and I forgot, I did add electronic ignition. I bought the distributor, coil, and ignition box for a 1984 Dodge D150 318 engine. I got the wiring from an old dodge that found at a salvage yard. It was easy to change from points to electronic ignition. It's weird, my brother has a '65 Dart GT. But it is an all original car with the 273 4bbl and a 4 speed. I tried to pretty much make it the same as his. My car has an automatic where his is manual. Otherwise they are the same and his never gives any overheating issues. The engine only has about 1000 miles on it even though it has been refreshed about 3 years. The temp will rise to a little more than half the gauge while in traffic. But, as soon as I begin moving it will begin to come down. It comes down quickly. After I drive it when I park it will push coolant out the overflow. If I am in traffic for a long period of time, or say in a drive through at a fast food, it will push coolant out the overflow.