75 hp. 1992 mercury 3 cyl only firing on one and three cylindar HELP!!!

[snailnut]

I have a 1992 75 hp. 3 cyl. Mercury boat motor that I took out yesterday and would not start again after fishing. It is firing on the one and three cylinder only. Any suggestions? any help.

 

[Texasmark]

Re: 75 hp. 1992 mercury 3 cyl only firing on one and three cylindar HELP!!!

Unplug your #2 CDI and put it in either slot ensuring that all the wiring for that slot stays with that slot. Move the module only. Then do your test again and if the problem follows #2 then that is your smoking gun. If not, you may have wiring issues or triggers missing from under the flywheel.

Mark

 

[Texasmark]

Re: 75 hp. 1992 mercury 3 cyl only firing on one and three cylindar HELP!!!

Unplug your #2 CDI and put it in either slot ensuring that all the wiring for that slot stays with that slot. Move the module only. Then do your test again and if the problem follows #2 then that is your smoking gun. If not, you may have wiring issues or triggers missing from under the flywheel.

Mark

 

[snailnut]

Re: 75 hp. 1992 mercury 3 cyl only firing on one and three cylindar HELP!!!

Where is the cdi box I know nothing about a merc I know where the switch box and rectifier is. We were at the lake started fine and fished for a few hours and then it wouldnt start just turn over, Thanks for your time.

 

[CharlieB]

Re: 75 hp. 1992 mercury 3 cyl only firing on one and three cylindar HELP!!!

92 is still a switchbox.

Follow the green wires on the coils back to the ignition switchbox, switch the green wires for coil 1 and coil 2 and see if the no spark has switch coils.

If not then the coil is suspect, remove, clean all connections, reconnect and retest.

If so, replace the green wires as original, notice the trigger wires coming from under the flywheel and connecting to the switchbox next to each coil wire. Switch the trigger wires for #1 and #2. Retest to see if the no spark has moved.

If not then the switchbox is suspect.

If so then the trigger is suspect.