The Stovebolt Site Forums The Shop Area General Truck Talk Radiator/Cooling in a 64 Please Help

Firstofall, does anyone know what temperatures are represented by the C --- H temp gauge? I assume the needle should ride halfway between the C & H, but mine is reaching nearly over to the H. Granted, it has been around 100 outside the past couple of weeks. I'm running an original triple-core radiator with a 13 psi cap. When I park, I usually lose a hand-sized puddle of coolant out the overflow hose. How do I know if the system should be burped? Also, someone told me to go to a 16 psi cap, does this sound better? Advice is mightily appreciated.

These dash gauges are just indicators. They can very a lot. Does the gauge go right up to the temp. & stay there all the time or does it run cooler & go up when it gets real hot out. A lazor thermometer would tell you what is happening or you can take off the cap & put a thermeter in the coolant & see how hot it gets & compare it with the gauge. Sometimes a new thermostat is defective. Iwould use a 180. I would not go to a higher pressure cap then that.

It reads cool at startup, then gradually works up to that high reading, which gives me confidence in its accuracy. Also, I forgot to mention the engine's a 350. I'm going over the thermostat right now, would you still recommend a 180?

I would recommend a slightly lower thermostat. The temp is when the thermostat opens and water begins to flow from the engine to the radiator. On a hot day (all summer), do you really want the water hitting 180 before flowing? I think the radiator and cooling system has to play catch-up at that point. I had a 160-degree in the 283 I just pulled out. In the high 90s, the engine would stay nice and cool.
I also installed a 7-blade fan and a fan clutch. I didn't get the fan shroud on yet...found out I need to modify it.

-Brad

It sounds like a stopped up radiator to me.

My buddy also says the radiator could be clogged. I checked the thermostat & it seems to open up at the right time, and running it with the cap off I could see circulation in the top of the radiator, but i didn't know how much circulation was enough. I flushed the rad before i put it in and it seem to flow pretty freely. Could a slight clog be the problem?

It really won't be clogged like a drain, but simply coated inside w/calcium or whatever deposits, this insulates the tubes inside & keeps them from radiating heat. Drain a little coolant out & look at the tubes for deposits. My 79 would run hot, the rad was rodded out 10+ yrs ago & had no leaks, it is 3 ft tall & 2 ft wide w/a 4 row core, good stat & fan clutch. I really just couldn't see it running hot w/that big of a radiator but it did. I really didn't want to buy a new rad($500+), but it solved the problem. Now it runs on the cool side.