RE: Diesel .50s (mostly)
Recyc, take the colored cooling fins off one of your PAWs and you will note that the engine is not tight at all. The piston is a very precise fit but has virtually zero drag on the cylinder wall. In fact if you place the piston halfway up the cylinder it will simply turn the crank and fall back down to the bottom, back plate off too of course. Another sign of this nearly friction free engine is when a PAW stops, the prop will bounce back and forth far more times than most other engines. What does all this mean, I dunno. All I know is that I broke three of them in like thay say to, and all three turned out perfect.