Wont fire on plugs

Paradise pontoon

Seaman Apprentice
Joined
Jun 27, 2023
Messages
45
Hello i have been working hard on a 3.0L mercruiser with HEI distributor. Had it running to set valves, installed everything back now no ignition! Purple wire going to coil is 12 volts with key on and cracking. White/ Green wire is 12 volts to distributor. Distributor is ground to engine good, module to distributor is also has a good ground. I installed new electronic module, new pickup coil , new coil, new rotor, new cap , new spark plug wires ( ohmmeter wires out) check good, new spark plugs, checked over and over connections,disconnected the tach wire, what im I missing?! Coil has good ground. Battery has 14.5 volts plenty of voltage. Replaced all battery cables positive and negative. Cleaned ground area. TIA
 

Scott06

Admiral
Joined
Apr 20, 2014
Messages
6,951
Hello i have been working hard on a 3.0L mercruiser with HEI distributor. Had it running to set valves, installed everything back now no ignition! Purple wire going to coil is 12 volts with key on and cracking. White/ Green wire is 12 volts to distributor. Distributor is ground to engine good, module to distributor is also has a good ground. I installed new electronic module, new pickup coil , new coil, new rotor, new cap , new spark plug wires ( ohmmeter wires out) check good, new spark plugs, checked over and over connections,disconnected the tach wire, what im I missing?! Coil has good ground. Battery has 14.5 volts plenty of voltage. Replaced all battery cables positive and negative. Cleaned ground area. TIA
Have you disconnected the shift interrupt switch ? If it is tripped it will kill spark. Disco it and test
 

Scott06

Admiral
Joined
Apr 20, 2014
Messages
6,951
Yes its by passed
When you say it was by passed you mean disconnected or did you connect the wires together Or jumper it out

attached is a wiring diagram for a 3.0 with a delco est , which is what I assume you meant by HEI igntion. If by chance you have an aftermarket HEI, will need to know what you have to help
 

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Paradise pontoon

Seaman Apprentice
Joined
Jun 27, 2023
Messages
45
When you say it was by passed you mean disconnected or did you connect the wires together Or jumper it out

attached is a wiring diagram for a 3.0 with a delco est , which is what I assume you meant by HEI igntion. If by chance you have an aftermarket HEI, will need to know what you have to help
Yes I contacted the two wires together. Its oem HEI . Just don’t understand,it’s simple system.
 

Paradise pontoon

Seaman Apprentice
Joined
Jun 27, 2023
Messages
45
When you say it was by passed you mean disconnected or did you connect the wires together Or jumper it out

attached is a wiring diagram for a 3.0 with a delco est , which is what I assume you meant by HEI igntion. If by chance you have an aftermarket HEI, will need to know what you have to help
Yes that is the system i have
 

Paradise pontoon

Seaman Apprentice
Joined
Jun 27, 2023
Messages
45
JustDisconnect the wires when connected together it will supply the 12 v to kill the igntion
Good morning, ok i have disconnected the purple wire and white wire. Still no spark. Put another new module on this morning with another new rotor. Still nothing!! Im getting parts from part store they probably fit a car engine would that make any difference? I see all the time other people say it works the same
 
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