ignition wiring question

bcasurvey

Seaman Apprentice
Joined
Dec 14, 2011
Messages
37
hey guys , i'm working on a 1989 190 baja 4.3 ltr
1. there are two wires wht/grn in the same wiring harness as my coil wires but they are NOT the amp module and safety switch wires. i've read the manual but they are not in there. 4 wires wont fit on the right distributor post and i dont know what to do with they, any ideas?
 

shopboy

Seaman Apprentice
Joined
Apr 28, 2010
Messages
30
Re: ignition wiring question

after a quick look at a different Mercruiser wiring diagram, I would guess that the white/green wire goes to the shift cutout switch (interruptor)

Its job is to kill the ignition for a quick moment while shifting in order to allow the gears in the outdrive to unmesh.

I think most Mercruiser wiring colors after a certain year are universal (BIA) But I would look for a wiring diagram for your exact motor
 

Pete104

Lieutenant
Joined
Apr 30, 2011
Messages
1,439
Re: ignition wiring question

If you are still running thunder IV ignition, the gr/wht wire has to be sistered with gr/wht @ the dist. sensor.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: ignition wiring question

Not sure what manual you are looking at, but you shouldn't have more than 2 wires on any terminal on the distributor itself, or the coil either for that matter.
You are right on a change year of wiring, and boat year doesn't always mean engine year. Here are the two OEM wiring diagrams, which one is like yours as far as the ignition Amplifier goes?

EDIT: Got to love when the images don't show. There are two .pdf files there, move your mouse cursor over the thumbnails to see both.
 

Attachments

  • Pre89.pdf
    188.8 KB · Views: 0
  • 89up.pdf
    185.4 KB · Views: 0

bcasurvey

Seaman Apprentice
Joined
Dec 14, 2011
Messages
37
Re: ignition wiring question

it's the 89 and up dia. but these wht/grn wires are not from the terminal block and amp mod. and they are in the coil wire harness???
yes thunderbolt iv but this would put 4 wires on the right side terminal of dist.
maybe they are dead because of year change???
 

bcasurvey

Seaman Apprentice
Joined
Dec 14, 2011
Messages
37
Re: ignition wiring question

after a quick look at a different Mercruiser wiring diagram, I would guess that the white/green wire goes to the shift cutout switch (interruptor)

Its job is to kill the ignition for a quick moment while shifting in order to allow the gears in the outdrive to unmesh.

I think most Mercruiser wiring colors after a certain year are universal (BIA) But I would look for a wiring diagram for your exact motor

where did you find this i would like to see it?
 

bcasurvey

Seaman Apprentice
Joined
Dec 14, 2011
Messages
37
Re: ignition wiring question

so i got the motor started without previously stated wires, but the motor would not shut off with the key. i'm not sure if its related.
can anyone tell me which circuit kills power to the coil in the diagrams?instr wire.JPGelec.JPG

i dont see what kills power and motor wont shut off.
there is a pur wire from altenator to + coil if it stays hot when running what shut off the motor??? thanks...
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: ignition wiring question

The purple wire get's power from the ignition switch. Turn the switch off, and the power stops (unless the ignition switch is bad).
The one going to the alternator is only a sensing wire for the alternator, and the wire is not powered by the alternator.

Post some pictures of your wiring, and make them big enough to see. Because it sounds like it's all messed up.
 

bcasurvey

Seaman Apprentice
Joined
Dec 14, 2011
Messages
37
Re: ignition wiring question

it's the 89 and up dia. but these wht/grn wires are not from the terminal block and amp mod. and they are in the coil wire harness???
yes thunderbolt iv but this would put 4 wires on the right side terminal of dist.
maybe they are dead because of year change???


update someone ran a wire from the terminal block to then coil, leaving two wires wht/grn which is one wire looped in the harness. on to the next gremlin...
 
Top