Sorry for the delay, it being Christmas and all! The wife seems to think that family is more important than iboats, geesh! lol
Anyways, put your black probe on an engine ground, the bolt or cable grounding the starter motor to the engine is a good point, and your red lead on the large input for the starter motor. Note the reading. =12.80 Also let us know the reading of your battery when sitting. Should be around 12.65 volts. = 12.80
Voltage Drop Test
First set your DVM to the 20 Volt scale
Put your POS voltmeter lead on the battery POS terminal and the voltmeter NEG lead on the large incoming solenoid/battery terminal post and give her juice. If the meter reads more than .3 volts, the battery cable is bad, corroded or you have a faulty connection (loose). = .3-.8...i then changed battery cables and got .3-.6
Next, connect the POS lead to the incoming large solenoid post and the NEG lead to the outgoing large solenoid post while giving her juice. If the voltmeter reads greater than .2 volts, the solenoid is bad, corroded or has a faulty connection. Had problems getting this check? don't think i was doing it right...but I do know my selonoid is brand new i just bought it.
Next, connect the POS lead to the outgoing large solenoid post and the negative voltmeter lead to the starter positive post and give her juice. A reading of over .2 volts indicates faulty wiring between the solenoid and the starter.= .02-.04
Finally, connect the NEG lead to the NEG battery post and the POS lead to the engine block and crank the engine. A reading greater than .3 volts indicates a faulty negative cable, corrosion or a faulty connection.=.32..then after with the new wires i got .1