20 hp IC twin cyl. b&g model 461707 type 0143- E1 When I turn the key starter engages and spins motor 1/4 turn, if I hold the key to on nothing happens and I am afraid to burn starter, I turn key off then back on the motor seems to until it gets past compression stroke, really struggling to start then finally it will start, I let run to warm up and try again thinking oil to thick same results maybe a little improvement, Tried 2 batteries both fresh one brand new, 235 CCA, and 275 CCA thinking not enough amps to turn the twins. Is it possible the starter windings are bad, no overhead valves, not sure if there is a compression release, and is there a way to test before taking the new starter route.