crh 318 was converted to elec ing before I got it . having prob with coil cutting out . can take boat out runs fine 1/2 throt full throt. comeing in I have 15 min.ride up lagoon at idle .will cut out no spark oi red hot change coil starts right up at idle only batt voltage on plus side of coil some times 3.9 or 1.9 volts on neg side .cking coil on a crusader charge voltage in on plus. 6 volts out on neg. what is min voltage n neg side? ps have new cap rotor and wires thanks for any help