new vs. old thunderbolt ignition sensor

dmiles452

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I recently replaced the sensor on my thunderbolt ignition. The old unit had two terminals, one terminal had two green/white wires and the second terminal had one with one white/red wire. The new unit has one red/white and one green/white both are pig tails with connectors on ends. Where does the second green/white go? and what does it do?
 

Scott Danforth

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read the instructions that come with it.

the old was a 2-wire, the new is a 3-wire and the 3rd wire goes to ground
 

dubs283

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Where does the second green/white go? and what does it do?
One wht/grn goes to ignition module, other wht/grn is for shift interrupt switch. If the wires from the module/shift interrupt have ring terminals use the adapter kit from the new module to connect to the bullet connectors. Double up the wht/grn wires to make the connection. Black goes to ground, preferably to the flywheel cover main ground for the battery
 

dmiles452

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read the instructions that come with it.

the old was a 2-wire, the new is a 3-wire and the 3rd wire goes to ground
The instructions were a joke, a whole page showing how to shrink wrap the connections and nothing to note any upgrade to the wiring. No description describing wire color. Very poor
 

dmiles452

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One wht/grn goes to ignition module, other wht/grn is for shift interrupt switch. If the wires from the module/shift interrupt have ring terminals use the adapter kit from the new module to connect to the bullet connectors. Double up the wht/grn wires to make the connection. Black goes to ground, preferably to the flywheel cover main ground for the battery
Is there anything that would stop fuel flow in the ignition circuit?
 

dmiles452

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I replaced the sensor in the dist. and now the engine seems to be getting no fuel. Pouring a small amount down the carb will get it to start but then it dies.
 

Bondo

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I replaced the sensor in the dist. and now the engine seems to be getting no fuel. Pouring a small amount down the carb will get it to start but then it dies.
Ayuh,.... Again,.... What motor,..??
 

nola mike

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Ayuh,.... The ignition circuit includes more than just the T-bolt system,.....
True. I was thinking he meant does the TB system limit fuel normally. But yeah, op switch/fuel pump/choke would come to mind otherwise
 

Scott Danforth

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Is there anything that would stop fuel flow in the ignition circuit?
1989 5.7 Mercruser
I replaced the sensor in the dist. and now the engine seems to be getting no fuel. Pouring a small amount down the carb will get it to start but then it dies.
your motor has a mechanical fuel pump unless you or someone changed it.

either your pump is bad (low probability), or the fuel filter is plugged (higher probability), or your float is stuck (high probability), or your anti-siphon valve is stuck (high probability)
 

dmiles452

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your motor has a mechanical fuel pump unless you or someone changed it.

either your pump is bad (low probability), or the fuel filter is plugged (higher probability), or your float is stuck (high probability), or your anti-siphon valve is stuck (high probability)
where would the anti siphon valve be located?
 

dmiles452

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Today’s update: I took the fuel line loose at the carb and turned the engine over. I got nothing, nota. So it appears on top of the ignition problem,the fuel pump may be an issue as well. I put a little fuel in the carb and while the engine was trying to run there was no fuel coming out of the line I had taken loose.
 
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