I posted this to the wrong forum, so I moved it to here.

I'm having an electrical problem with my boat. I just swapped out my motors and when I try to turn them over, the slave solenoids click but the starters do not turn. I turned the keys to the off position and I jumped the slave solenoid and the motors turned over. I checked the voltage at the solenoid and it was 13. When I turned the keys to the run position, the voltage dropped to 9. Any ideas what to check? Any help appreciated.

That is an odd problem. Just to be clear, when the ign switch is turned to "run" (not start), the batt cable at the starter solenoid drops from 13 to 9 volts??

What happens to the batt voltage if you jump the starter solenoid and crank the engs over?

When you turn the key to start, do the solenoids click once or do they chatter? You definitely have a supply issue, whether it's the battery or cable you will have to check. I am running 10:1 compression with a distributor locked at 34 degrees and I don't drop below 10 volts.

I just changed a starter, you don't have aftermarket starters in by chance? I just ran into almost the exact same scenario. The aftermarket starters have 4 posts instead of 3 and I had then trigger wire on the wrong post. When you hit the key the voltage would drop to about 9 on my gage and I'd get 1 click. Once I swapped the wire to the other pole everything worked fine.

That was my original problem. After I moved the yellow/red wire to the solenoid post on the starter, is when I started getting the low voltage issue. I also noticed that the coil was getting very hot.

the slave solenoid(s) may not be grounded. 89 is thunderbolt 4. coils shouldn't heat up. u got something hooked up wrong.

I had a wire connected to the coil that shouldn't have been connected to it. Once I removed it everything seems to be working correctly.