Despite the fact that this problem was limited to the first prototype only, a symptom of the speed with which the first car was put together, the damage to the car's reputation was done, and a storm of negative media followed. Tucker suffered another setback when his bids to obtain two steel mills to provide raw materials for his cars were rejected by the War Assets Administration under a shroud of questionable politics. Tucker had promised , but his innovative engine was not working out. The valve train proved problematic and the engine only produced approximately . The high oil pressure required a 24-volt electrical system, up to 60 volts to get it started, and a long cranking time at start-up. Additionally, the oil pressure required to maintain valve function was not achieved until the engine was turning at higher RPM and Tucker's engineers struggled with keeping the valve train working at idle and lower speeds/RPM. Having wasted nearly a year trying to make the 589 work, Tucker started looking for alternatives. The company first tried the Lycoming aircraft engine, but it would not fit in the car's rear engine compartment. An air-cooled flat-6 engine, the O-335 made by Air Cooled Motors (and originally intended for the Bell 47), fit, and its pleased Tucker. He purchased four samples for $5,000 each, and his engineers converted the engine to water cooling (a decision that has puzzled historians ever since). The Franklin engine was heavily modified by Tucker's engineers, including Eddie Offutt and Tucker's son Preston, Jr. at his Ypsilanti machine shop. Using an aircraft engine in an automotive application required significant modification; thus, very few parts of the original Franklin engine were retained in the final Tucker engine. This durable modification of the engine was tested at maximum power for 150 hours, the equivalent of , at full throttle. Tucker quickly bought Air Cooled Motors for $1.8 million to secure the engine source, then canceled all of the company's aircraft contracts so its resources could be focused on making automotive engines. This was a significant decision, since at the time of Tucker's purchase, Franklin held over 65% of post-war U.S. aviation engine production contracts. The loss of income was substantial. With the horizontal, between-the-wheels 589 motor and its double torque converter(s) (and no reverse) drive system out, Tucker now needed a transmission to mate with the Franklin O-335. This motor was also horizontal, but its driveshaft pointed towards the front of the car.