Packard Forum Index » Post-War (1946-54)

My car started overheating last summer, out of the blue. It was running fine and suddenly started to run 200+ when moving down the road. 2 summers ago I pulled the radiator out and had it checked, replaced the water pump and pulled the distribution tube and flushed everything, it all seemed OK and ran fine for a long time. It just decided to run hot late last summer. I changed thermostat, flushed etc but nothing helped. Timing is good, and the car runs well. I am thinking I will need to recore the radiator in the spring but wonder if I am missing something that I should check before I do that. I am checking the temp with an infrared thermometer and have an aftermarket thermometer in the head, they both agree. I would welcome any suggestions, thanks.

Have you checked the gauge or sender? Maybe it's not actually running hot but the gauge is intermittent!

Otherwise, there is a possibility that something is stuck or moving around in the distribution tube behind the water pump which will require removing the radiator, pump and anything else that might be in the way of pulling it out for inspection.

One other possibility is that your distributor is not advancing as it should. You have centrifugal advance operated by springs in the bottom of the distributor. That system might need work. The second is the vacuum advance which runs with a tiny pipe from the bottom of the carburetor up over the engine to the distributor. It could also be causing less than normal advance, it could need inspection and a good cleaning. Just my own experience. Ernie in Arizona

I had the same problem with my 49 deluxe 4 door sedan. After eliminating all other possible causes for overheating,I was left with one last possible cause, valve clearance.Mine were adjusted to .005 and.007. Too tight,didnt give the valves enough time in the seats to diffuse heat.Adjusted them to .009 and.013.larger number is for exhaust valves.Worked great problem solved.I assume that you know that these cars tend to run hotter than other makes.Mid range on the temp gauge is normal,and in the hot summer past mid range is ok.It says so right in the owners manual.Good luck