ignition coil wiring OMC 350 5.7L

How does the wiring work on a coil. 2 wires on the + and 2 on the -. what are these 4 wires. and what voltage should be where when Please.

Re: ignition coil wiring OMC 350 5.7L

Not sure what engine and setup you have, but here is a common setup...<br /><br />The positive wires:<br /><br />One comes from the starter. This supplies the coil with a full 12 volts for starting. After the engine starts, the coil receives power from the other wire....<br /><br />The other wire is a resistance wire, (or possibly a wire coming from a ballast resistor - either way, the result is the same, a lowering of voltage). The best way to check the voltage of that wire is with the engine running. There should be a drop in voltage - I'm not sure of the ammount of drop - it seems like it goes to 9 volts - maybe even as low as 6. If you need to check it without the engine running, I believe you need to make sure that the points are closed to get an accurate reading.<br /><br />On the negative side:<br /><br />One wire comes from your distributor (points)<br /><br />The other wire (I'm going from memory here - forgive if I'm wrong) is from your shift interupt switch.

Re: ignition coil wiring OMC 350 5.7L

On the +, one wire is the resistor wire which feeds a dropped voltage to the coil while the engine is running, the other is a wire from the starter which feeds a full +12V while cranking. <br /><br />On the -, one is from the shift interrupt (ESA) and the other is the tach wire. Also, there is a third wire there (should be) that goes to the points in the distributor.