77 stringer electrical run on

Joined
Apr 26, 2017
Messages
15
After some scares out on the water with the starter not engaging, I decided to fix the issue with a new ignition cylinder and a starter solenoid (the one separate from the motor). After they were installed, I started the engine after some quick unresponsive clicks. The motor finally started moving and then fired right up. After running it a bit, I went to turn it off and got nothing. The engine continued to run until I pulled the coil to cap wire.
Now for the diagnostic confusion! Probing around where I changed components, I found 12 volts at the battery terminal on the key and 9 volts at the ignition. With the battery disconnected (to avoid frying the coil) I've got continuity across batt and ign terminals. When I turn the key to start, the ign continuity to batt is cut. Going back to the engine compartment, I have 9v at the positive coil terminal and 1v at the negative terminal. Going to the ballast resistor, 12v at one end and 9v at the other. I've also got continuity across the two resistor connectors when one is disconnected. Going to the starter relay aforementioned above, I have continuity across the two large power terminals.
What is going on here?!
My current target is the solenoid on the starter motor, could this be the cause?
 
Joined
Apr 26, 2017
Messages
15
Development, Starter is an autolite model so there is no secondary starter relay. Now I'm just at a loss as to what to test
 

kenny nunez

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Joined
Jun 20, 2017
Messages
3,338
THe solenoid may be defective, the "I" terminal may be shorted internally. Start the engine and disconnect the wire, wear rubber gloves because there is voltage from the coil and try turning off the ignition switch.
 
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Joined
Apr 26, 2017
Messages
15
You nailed that one. Pulled the solenoid off and found a dead short from I to the positive battery terminal. New one in the mail, but I'm not sure how this one welded itself. I want to avoid trashing another one. What are the common causes of this?
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,338
If it is the correct solenoid you should not have a problem. The solenoid used on the Ford engines are the "grounded base" style. On the non grounded base style the "I" terminal is the ground. They look alike and are easy to mix up. Connect the wires but leave the "I" terminal disconnected and see if the solenoid clicks. If it does not you have the wrong one. If it clicks go ahead and connect the "I" terminal.
 
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