All early aircraft engines and C1 tank engines use a 6 7/8 inch impeller with 12 vanes. I do not have a C4 impeller but the manual shows what appears to be a larger diameter impeller with 16 vanes. Can anyone provide outside dimensions? The -46 impeller is 8 1/8 inches diameter and has 16 vanes. It also has holes through to the back.
Valves in the -46 and C4 have larger diameter stems than C1, and are not interchangable. I believe the -46 exh valve has an even larger diam stem than a C4.
Crankshafts, of course much longer in aircraft applications than tank engines but the C4 and -46 use a single nut and sleeve to hold the two front bearings in versus the earlier two nut method of the C1. Could you cut down a -46 to work in a C4?? Not sure.
