VCCA Home Forums Thread Like Summary - Overheating issue

I have a 1950 Chevy Styleline Deluxe with a 216 engine. I have replaced the radiator, water pump, thermostat, etc., etc. Unfortunately. when I start it and it runs for 10 minutes or so it overheats. Not sure what the problem is but any ideas would be much appreciated. Thanks, Mike

Drill a 1/8 inch hole in the flat flange of the thermostat or just remove the themostat and give it a try.
Some times the modern style thermostats do not open in the old non-pressure type systems.
That was my problem in my 1950..

When you say "overheats" are you referring to what the rad is doing or what the temperature gauge is showing you. If it's the temperature gauge climbing toward the H mark, take the car for a drive and see if the gauge comes back to the middle mark. If it does, your '50 is behaving properly. If not, check for a collapsed rad hose. If you're still having a problem, go back over the rad, water pump and thermostat to ensure they are operating properly. Even "new" ones can be bad.

Are you physically measuring the coolant temp and it's too hot or is it just overflowing the radiator? If it's simply overflowing the radiator you might just be overfilling it. Hot liquid expands and has to go somewhere. That issue is much more common that most people think. I'll move this to a technical forum for you.

Hopefully you do not have a real overheating problem. Unfortunately that typically is not the situation especially if an engine has set for a long time.

I was able to “save” a large amount of work on my ‘37 by flushing the block in 6 directions.

I removed both the thermostat and the water pump. I made an adapter plate that bolted to the front of the block where the water pump mounts.

I spent a lot of time finding various plumbing adapters so I could connect a garden hose at the thermostat housing outlet, the water pump adapter plate, and the drain port at the rear of the ranging block. Plus I had caps to block off each one of them.

It was a messy process but worked. I never had overheating issues.

I would be cautious about running the engine too much before trying to flush it. You run the risk of filling your radiator with crud from the engine.