You are right the carb is the 7D with a sleeve in the venturi area, same size as my 1.08. With just my eye, the crankshaft gas passage does not look to be that small. I will measure the I.D. and post back later. The carb throat is pretty large for a 15cc engine, I may swap it for a 7L to compare RPMs and fuel draw when I put this engine into service.