as stated before the best way to test the starter is to jump it with cables, i have done this many of times, espically when i am looking for an engine in the pick yards, i tote a battery with cable and jump the starter with it to check compression its pretty much safe the only way your going to hurt yourself is if you ground youself out and then use an object which has no insulation on the handle ( chances are your screwed driver has a platic handle no problem there ) even then where your jumping it is actually only 12 v's as it is direct from the battery, it is only the syl your jumping, just dont mess with the stater itself as thats where the serious voltage is.