RE: O.S. 91 four stroke pump problems
Once you know the engine well, you can set up your glow four-stroke to start simply by twisting the spinner backwards against compression. It takes a little time to get the knack, but that is how many folks start their two and four-stroke engines these days.
Properly applied, an electric starter will not hurt your ball bearing engine. But it won't do your spinners any favors, that's for sure.
Ed Cregger