John K Wrote:
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> Interesting that the Oahu engines, while very
> close to identical in most ways, have greater
> weight on the drivers vs a K28. Were K28s
> considered "slippery" that a higher factor of
> adhesion is needed??? Or is it an effect of air
> pumps being mounted "midship" vs on the smoke box
> front?? Or both?
The D&RGW engines carried more weight on the pilot truck than the ORY engines, therefore the ORY engines had more weight on the drivers. In knockdown, dragout, slugfest, and Oahu engine might pull a bit more because it had more adhesion on the drivers. The difference might be in the way the equalization between the pilot truck and the drivers was set up, or because of the that big cross compound air pump on a K-28's nose. Also the Oahu engines had a smaller, lighter tender to drag around.
It is interesting to note a 8 1/2" cross compound air pump weighs about 2700 pounds. Very close the the weight difference.
In some circles, it is thought the extra weight on a K-28's pilot truck contributes to the superior riding qualities of the engines.
Comparing total engine weight to weight carried by the pilot truck, the K-28's had the greatest percentage of weight on the pilot truck, the K37's had the least amount of weight.
Edited 1 time(s). Last edit at 10/20/2019 11:19AM by Earl.