its a 53 261 with a short shaft pump and a 160 degree thermostat
Does "short shaft pump" mean a 1954 to 1955-1st water pump? Any chance you could post a photo of the front of the engine?
How did you identify the engine as from 1953? What are the head and block casting and date codes (
here are the locations)?
If the water pump is mounted high (as in 54/55), and the fan belt is good, and the thermostat is good, and the radiator is good, your engine could be clogged up internally (mine was, especially at the rear of the block).
Tim
