yes, without a thermostat the water velocity is too great to be able to pickup heat. Also, I would guess there was an overheat problem to begin with and the prior owner pulled the T-stat to get bye for a short period. My guess the rad is plugged..

I would flush the engine, replace the T-stat and have the radiator serviced. While at it, it would be a good time to change the water pump as well. As regard to the two-blade fan. I do not know what was original, however that sounds not right.

The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me