Packard model 2365, 288 cubic inch engine running hot

Posted by Joe D'Agostino On 2015/5/30 21:58:06

My 1949 23rd series, 288 cubic inch engine is running hot when idling. I have had the radiator re-cored, installed a new water pump, had the water distribution tube removed and during removal had the center of the block power washed until clear water ran from the thermostat channel.

A lot of gunk came out during the power wash.

We let some of it come out of the front of the engine and some come out through the thermostat housing area.

But then the water ran clean.

Still the engine runs hot when idling in mildly warm weather (85 degrees ambient)

At this point, is it worth pulling the head? Are there any ports in the flat head that may be restricted and not be allowing good flow of cooling liquid?

I am not sure of the return path of the liquid once it runs through the water distribution tube and I am thinking that the flat head may have some restrictions.

I would appreciate any comments.