Mercruiser 5.7L with low voltage to coil

[Gunner54]

I measure 12.5V at the battery and 11.3V at the coil and with key left on for a bit the voltage drops to 10.8V.

Any suggestions why I'm not seeing battery voltage at the coil and the voltage is being lost? Where to check?

 

[Scott Danforth]

Year or serial number

If you have points, the resistor wire

If not, bad connection

 

[Gunner54]

Thanks, the engine uses an upgraded MSD 83606 marine distributor and coil.
It's run fine until this season.
Any suggestions where to start in sourcing a phantom bad connection?
Would there be any wiring schematics floating around for this?

 

[alldodge]

If the distributor installed without the resistor wire, then see if the coil is getting hot

 

[Scott Danforth]

Thanks, the engine uses an upgraded MSD 83606 marine distributor and coil.
It's run fine until this season.
Any suggestions where to start in sourcing a phantom bad connection?
Would there be any wiring schematics floating around for this?

MSD generally is referenced as "My Spark Disappeared" in the pits