Associated Manufacturing Company. 1924 Amanco Iowa Oversize 6hp Engine No. 420755A. First Start.

Engine No. 420755A. Year. 1924. 6hp at 470rpm
Manufactured by the Associated Manufacturing Company of Waterloo, Iowa.
In 1923 the Amanco 4hp was re-rated 6hp and underwent several design changes, in doing so, this was designated to “Iowa Oversize” engine. The water hopper was extended to overcome the cooling problems, the valve diameters were increased and the bore was enlarged from 4.3/4” to 5”. The flywheels were made heavier and speed of the engine was increased from 400rpm to 470rpm, this all achieving the increase in power