RE: 1/2A Diesel Engines?
I haven't tried the .074 conversion, that one is likely a winner if you don't go overboard with prop selection. It isn't just the combustion pressure that does the 1/2A engines in, but combine that with the greater work load, and that is what does them in. I haven't tried making my own thicker rod yet, for some reason I haven't had any crank failures with the NORVELS. A local 1/2A guru thinks the AME is the best engine to dieselize, and he himself has a pile of snapped rods to show you. He dry cranks the engines with the feed line pinched, and allows the fuel to get pulled into the engine, does not prime it or allow a fueled up model to sit around fueled up unless the feed line is clamped off.