The story I read about the Atlas Imperial Diesel-powered Kaiser Sixtys, was that they were not a success, because the Atlas engine was too heavy, had too much torque, and tore the Sixtys apart, making them far less reliable than the genuine article.
The Atlas was designed purely as a marine engine .. and weight, torque and vibration were not major concerns in that application.
Air start was a feature of the Atlas that was less than desirable as a tractor starting system, in Caterpillar engineers eyes .. and lack of a decent intake air cleaning system was another factor that was regarded as highly undesirable in a tractor diesel.
A 1933 Cat Diesel brochure I have, describes the factors that Cat considered paramount, for the design of a crawler tractor diesel engine .. these factors were ..
1. Ability to maintain load for long periods of time, without without a drop in power, or smoky exhaust ..
2. An ability to idle smoothly, without irregular running or missing ..
3. An ability to handle variable loads with accurate governing, and quick responsiveness, under frequent load changes ..
4. An ability to run smoothly without pounding or roughness in operation ..
5. It must be able to handle a wide variety of diesel-type, low cost fuels (as there were no set standards or benchmarks for diesel fuel, as is the case today) ..
6. It must be free from the necessity of frequent delicate checks and adjustments, and free from operating annoyances ..
7. It must have a simple, reliable and positive means of starting, easily operated, and capable of functioning continuously for whatever period was necessary (note, that air start was NOT regarded as a reliable system by Cat!) ..
8. The Cat diesels maintenance costs had to be low, to meet the expectations of Caterpillar owners .. as low operating costs were a major advantage in owning a Cat.
Needless to say, light weight was also a major consideration in the Cat diesel design .. as all other diesels up to that point, were all considered to be too heavy for crawler tractor use.
The end result was that 4 other manufacturers diesels were purchased, and their operating systems studied, and their weaknesses found (for tractor operation) .. and every type of diesel fuel injection, and combustion system, examined .. before low pressure mechanical injection, and precombustion chamber design, was decided on, as the perfect requirement ..
At that point, Cat did many thousands of hours of research into diesel fuel flame propagation and combustion .. and even designed testing equipment that did not previously exist, to examine the actual combustion process at speeds of hundredths of a second .. a pioneering feat in that era ..
The Cat diesel was one of the most expensive and thorough design developments, to be undertaken at the height of the Great Depression .. and is testament to Cat management, that they saw the project to highly successful completion, at a time when many other manufacturers were dropping like flies ..