Mercruiser Alpha One Thuderbolt IV need electical advise engine suddenly stopps

monette999

Seaman Apprentice
Joined
Jul 8, 2011
Messages
35
Dear Forum,
I am Bob quite new here and living in Germany. I am joining this forum since V8 boats & experts are hard to find here. After rebuilding my motor I was running my boat for a season without a proplem. Now it gives me some issues.
It is stops running like somebody turns off the ignition.Then I can start it asgain with no issues. Then it does it again. It is hard to catch the failure with a scope since it comes & goes.

My idea is to brigde the electric circuit to knock down the root cause. I would like to supply the Hall Sensor & the Tunderbolt Ignition (22° advancing) with a seperate power.

I would like to put 12V directly to the purple wire of the Ignition Amplifier!

Please correct me if I am wrong. The ignition module supplys the hall sensor in the dizzy. Correct??? What is the imput voltage of the hall sensors 5V or 12V?
And is the supply cable the WHT/RED cable.

The Hall Signal is the WHT/GRN. If I splice this cable how shall the hall signal looks like (12V or 5V) output.

Thank you forum for your responses. I would like to avoid switching all kind of parts and then realizing I have a cable break to bad terminal.

Here some pictures to visualize my problem discription.

BR
Bob
 

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monette999

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Messages
35
No Title

Here my photos
 

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MikDee

Banned
Joined
Jun 6, 2007
Messages
4,745
Maybe it's a faulty ignition switch? Or your coil is breaking down?
 

monette999

Seaman Apprentice
Joined
Jul 8, 2011
Messages
35
I thought it could be the shift cutout switch. How is the test prosedure of this switch.
 
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