1989 mercruiser 5.7 ignition

[Usarmygordon]

So about a month ago I had this engine running for about 10 secs and then it died, the only thing that I replaced since then is the coil pack.
So now I am not getting spark to my plugs.
I’ve replaced the batteries, plugs, wires, coil pack, cap, rotor, sensor and the tach and it’s set to 8cyl
I’ve unplugged my tach wire and the neutral safety switch wire.
I have 12v coming from the postive side of the coil pack and from the coil pack to distributor wire. And I’m getting voltage to the sensor as well.
Plugs have been gapped correctly
I have also tried adjusting the timing on the distributor but I still got nothing.

I also have 12v coming from the neg side of the coil pack- i don’t know if I’m supposed to or not- troubling shooting steps don’t say anything about that

 

[Fun Times]

Do you happen to know if maybe spark is coming out of the coil wire/tower directly? or just you're checking at the spark plugs themselves only?

own a timing light? for quick first reference test you could try using the light to see if there's any flashing while hooked to the high tension coil wire then check each plug wire.

Just a quick note... I believe there may be a ground wire to the ignition module that's unbolted from the engine.

I "Unplugged" the neutral safety switch wire....
Was this at the helm shifter or at the engine shifting plate bolted to the other {starboard} exhaust manifold?

If the mercruiser shift interrupter switch is activated or compromised, it will not allow spark...,Mercruiser shift switch. Shift Interuptor switch (sterndrive-information.com)

 

[Usarmygordon]

I used a spark plug tester that has the light bulb in it from the distributor to the individual wire for the cylinders and got nothing. And that ground wire on the module is connected.and I unplugged it from the actual switch on the starboard exhaust elbow

 

[Usarmygordon]

Do you happen to know if maybe spark is coming out of the coil wire/tower directly? or just you're checking at the spark plugs themselves only?

own a timing light? for quick first reference test you could try using the light to see if there's any flashing while hooked to the high tension coil wire then check each plug wire.

Just a quick note... I believe there may be a ground wire to the ignition module that's unbolted from the engine.

I "Unplugged" the neutral safety switch wire....
Was this at the helm shifter or at the engine shifting plate bolted to the other {starboard} exhaust manifold?

If the mercruiser shift interrupter switch is activated or compromised, it will not allow spark...,Mercruiser shift switch. Shift Interuptor switch (sterndrive-information.com)

View attachment 339231

So I got it diagnosed to the nuetral safety switch, I have spark now

 

[Bondo]

So I got it diagnosed to the nuetral safety switch, I have spark now

Ayuh,..... Welcome Aboard,..... That's certainly odd, as the neutral safety switch is in the starter crankin' circuit, 'n has nothin' to do with the ignition circuit,.....

 

[Usarmygordon]

Ayuh,..... Welcome Aboard,..... That's certainly odd, as the neutral safety switch is in the starter crankin' circuit, 'n has nothin' to do with the ignition circuit,.....

I did this part of the troubleshooting and had my nuetral safety switch unplugged and when I (rapidly tapped it) my ignition sensor wire in the distributor it caused spark

 

[Usarmygordon]

And I think when I plugged my sensor back in, and had the spark gap tester in I had spark

 

[Bondo]

I did this part of the troubleshooting and had my nuetral safety switch unplugged and when I (rapidly tapped it) my ignition sensor wire in the distributor it caused spark

Ayuh,...... The Shift Interrupt switch,.....

That's in the ignition circuit,.....

The neutral safety switch is in the controller housin', 'n is in the Start circuit,....

 

[achris]