Mercury Ignition wiring

[nebbe]

I have a 1983 Mercury electric start outboard. It has been sitting for a couple years and several wires from the ignition system are cracked, corroded, etc. The motor turns over very slowly when both plugs are installed, but with the plugs removed, it turns over strong. I have had it running, and it runs great, but it's been random as to when it starts and runs. It seems to me that the corrosion, etc. are providing too much resistance for the starter and ignition to get enough power. Is there a re-wiring kit available? If not any, recommendations as to the type of wire to use to accomplish this? Thank you.

 

[mark_gober]

Re: Mercury Ignition wiring

Nebbe,

Let me tell you how I'd troubleshoot this. Obviously this system runs on 12 volts. Go back to your starter and put a multimeter at the starter 12v connection. Then hit the starter. You should see 12 volts. If you have excessive corrosion on the cable, you will see less voltage there. Another option would be reading the resistance from the starter cable back to the solenoid and then from the solenoid back to the battery. You should read almost zero ohms. Probably less than 2 ohms. A high resistance reading confirms your thoughts.

Mark

P.S. Also, check the connectors right at the battery. Their proximity to the off gasing of the batteries will cause them to corrode much faster than other locations. It's almost always the location of problems.

 

[Chris1956]

Re: Mercury Ignition wiring

Nebbe, Also inspect the entire length of the battery cables. A bulge under the insulation indicates corrosion, which will cause high resistance. I had a battery cable that rotted out to only 2 strands. Guess what, my starter turned real slow.

 

[don-t]

Re: Mercury Ignition wiring

i have a old 50 hp 4 cyl. battery ignition the stater only charges batery, has switch box with red white blue and green ther is no voltage on green wire going to coil while cranking where does the voltage come from that goes to switch, coil and distribtor there is only 2 wires coming from stator and they go to recitifier red wire on recitifier goes to battery that is only place i have 12v except celonid for starter which works d-t