Ignition wiring problem

I have replaced the ignition switch on my 1997 Mariner 115 but cannot get the motor to fire.

I initially changed the switch because I could not trace the reason why I was not getting power at the switch. It turns out the yellow/red wire at the starter solenoid was not getting a good connection. Reworking that connection would have solved the problem right there but I had already started re-wiring the switch after overlooking this problem. At the time I was using the original wiring harness from a previously installed 1986 90 HP Mercury which had no issues until the loose wire got me to changing out the ignition switch. During the troubleshooting I also tried plugging in the wire harness from the Mariner which also had the temp alarm attached and everything seemed ready to go to re-wire the new switch to this harness to get use from the temp alarm which I did not previously have. I got everything hooked up to the new switch exactly as it was wired to the previous switch and two things changed. First, the alarm did not sound when the ignition was turned on and the more pressing issue is the starter motor runs but the motor makes no effort to fire.

Frustrated, I have used both harnesses now and still get the same results. Any ideas why the motor is not want to turn over even though the starter motor is engaging?

This was hard to condense and make somewhat understandable after working on the problem for the past few days, please feel free to ask any questions to help narrow the steps I have been taking.

Thanks for the help.

Re: Ignition wiring problem

you could try cleaning the ground connections and the battery connections.
When you say "engaging" is the starter cog spinning far enough up to contact and turn the flywheel?

Re: Ignition wiring problem

Is you battery up to full charge ? Start right from square one looking at everything you've done - particularly getting the correct coded wire hooked to the right spot. If the motor is making no effort to fire do you have a stop circuit problem? You could also have a CDI unit failure if there's no effort to fire...to check the CDI, you'll have to check everything but the CDI - trigger coil, ignition coils, main power coil .... a timely job ! Fresh plugs ? Check and clean all grounds. You'll need to get the resistances for the individual components ..got a Seldoc manual ? Got a good auto-ranging VOM ? If everything's OK, it's usually the CDI.

Re: Ignition wiring problem

The ignition switch grounds the kill circuit to kill the engine. If you wired power to that wire, you fried your switchbox.

The engine should start with the harness disconnected. Get a manual and understand where to jump it to crank it, and which wire on the switchbox to ground to kill it before you do such a thing.

Get a Mercury manual. Seloc manuals are good for the outhouse.

Re: Ignition wiring problem

Fixed!

Thanks for the replys. Following the wiring diagram on the new universal switch I had the ignition wire on the "I" terminal when it should have been on the "M/A" terminal and the accesories wires on the "M/A" terminal when it should have been on the "I" terminal. Easy enough to fix after reading around a bit more last night, but did not feel comfortable just randomly switching around wires.

Again, thanks to those that tried to help out.

Dave