Re: 1950 Packard 288 Auto overheating HELP

Posted by Tim Cole On 2011/2/14 18:23:45

Dear otgdy:

Wow! The 288 motor should not run hot. It is Packard's best all around straight 8. I drove some originals that had plenty of power and ran great on the freeway even without OD.

Obviously something is wrong. Take out the thermostat for starters. If the condition goes away replace the unit and drill a few 1/8 inch holes in the plate of the new one which is available from NAPA. I don't have the number handy.

Next, I guess you had the radiator out and with the water pump off shoved a steel rod to the end of the distribution tube. Sometimes motor rebuilders forget to put those things back in the motor which causes huge overheating.
Also, I have seen cases where mice got into the cooling system and the nest clogged the tube.

I assume the motor is in good shape. I coped with a 1911 that ran hotter than a cinder because of a vacuum leak and too slow burn rate. Is the timing chain and compression good?

Does the lower radiator outlet still have the intake pipe or has it been replaced with a single hose? I have had to make up the intake pipes to cure overheating caused by collapsed hoses.

Has the cylinder head been off? I dealt with a V-12 that was junked in 1956 because the aftermarket cast iron heads were not drilled on the left bank.

To be sure, when new these cars ran without overheating, however, as they age the metal itself starts loosing its transfer properties. But that won't cause it to boil like a volcano.

Are any exhaust vapors coming out of the radiator cap? I worked on an 11th series car that people said had a cracked block. I bought a carbon monoxide tester from McMaster Carr and tested for exhaust in the radiator. Nothing. So the problem boiled down to the overflow tube being too high in the radiator.

Good luck and I'm sure this problem can be figured out.