Starter Problem

Im sure the connections are not bad but who knew can i check that with a volt meter or something maybe..? And about my starter this one have a problem for sure is i mention on my posts below that when i put a ground cable to the starter and a positive cable to the motor of the starter the gear didnt came out of the starter but when i tried that on my broken one i have laying here around too the gears came out like it should

here i put the positive cable on


and the negative on the -connection plug on the starter it works on my broken one but not @ the one i have installed now

I think i will try to buy a new starter first, wich one is a good starter for magnum block and tti headers a body

thx Peter