1932- 901: hot running, overheating: advice sought.

Posted by tuskman On 2024/7/22 13:57:37

I recently acquired a 1932 Packard 901 Std. Eight. (320 cid). The previous owner advised that recently, the car would run hot in hot weather. My first ride was on a 91 degree humid day. I took a 10-12 mile ride at moderate cruising speed (35-45 mph). The temp gauge came up to approximately the ¾ level (near the top of the safe zone). It stayed there as long as the car was in motion. Upon stopping at a stop sign or slowing down and stopping pulling into the garage, the temp gauge rose rapidly into almost the overheat zone. I turned it right off and measured it with my laser thermometer. The hood handle was almost too hot to touch (130 degrees F). The hottest area was the front of the head at 215 degrees. The block was a bit cooler at 195-200, and the radiator and hoses were in the 190’s. My understanding is there is no thermostat in the engine only on the radiator to control the opening of the shutters. The shutters are now immobile or unhooked and are always in the full open position. What would be the normal operating temperature of this engine. Any ideas as to why it is running hot? Based on the fact it cools off some when in motion tells me the water pump is functioning to move the coolant through the radiator. Thinking maybe I need a chemical flush and then a backflush with fresh water. Any advice or tips would be appreciated. Could it be anything else other than a partial blockage in the engine or radiator? This is my first Packard of this (or any) vintage. Thank you!