bench test it first before putting it back in. put it in your Record vise, and put electricity to the hot lead. you'll have to make sure you're battery is grounded, and possibly have to ground the starter aswell. a lot easier than putting it in to find out. also, you should clean the copper armature where the brushes make contact, and then use a pic or skinny screwdriver to clean out each of the parallel lines between the the copper plates. it's important to clean those lines as they fill with debris and crud.