I'm sure there is, John Deere always leaves a little meat on the bone in their engines for reliability sake. The compressors we have, the engine is buried and covered by junk, hard to really get a good look at them.
That I cannot say. Looked for some info from Deere on them, I couldn't find anything. John Deere rarely produces that info and I cannot get a great breakdown of the gov. to see how they are put together.
After digging more too, those engines are very sluggish to gain rpms, smokey, and can be an absolute bear to get started.