Re: 1950 Packard 288 Auto overheating HELP

Posted by Owen_Dyneto On 2010/2/2 9:36:09

otdgy, to try to be more helpful, I've gone back and looked again at your original statement of the problem in post #1 of this thread, and find two statements that, if clarified, might help understand the problem better:

The problem is when I drive for a while and sit in idle (i.e. traffic) the car overheats.

and,

Car does NOT overheat if I start it and let it sit. Only after driving a while

No doubt you recognize tht prolonged idle is generally more stressful on a cooling system than driving along at a reasonable road speed, and that the higher the temperature difference between the coolant and the ambient air temperature, the more effective the heat transfer (somewhat simplified). I agree with your comments about the different rated thermostats and if the car was mine, I'd change to a 160 degree, not expecting it to solve the problem but at the least it would be give me a larger margin of operating temps.

You say the car runs fine - does it loose coolant? Steam from the tailpipe when first started? Any "wet" plugs after sitting overnight? Done a compression check? I'm thinking about a possible leaking head gasket. Does the lower radiator hose seem mushy? Does it have a stiffner in it to prevent it from collapsing under the suction of the pump?

Usually solving overheating problems isn't difficult, but I've worked on and off for several years with a friends 1950 Eight (288, standard shift) which runs cool at road speed but overheats at idle. We've been thru everything and I do mean nearly everything and thus far it has defied solution. New (4-row) radiator core. We've even magnafluxed the head looking for internal cracks, pulled welch plugs looking for obstructions, and much more. Though it's a lousy solution because it just masks a problem (and is tantamount to admitting defeat!), I think we've finally come to the conclusion to put on an electric pusher fan.