OK guys, I need help. 1983 Scarab III. All original. Several gauges quit working so I decided to go with all new Livorsi Gauges. Cleaned up the messy factory wiring. added port side positive, starboard side positive, lighting and grounding bus bars. Each engine fired right up and the gauges all worked and displayed correctly. Approximately 60 seconds in and the engines quit. It will not fire up. I feel I'm missing something stupid. I'm hoping I didn't fry the MERC ignition modules. I am going to go with MSD ignition, but I didn't want to do it yet. I'm not new to 12 volt electrical systems, but the wiring for the factory gauges was a sight to behold. With the key in the run position there is no power to the positive side of the coil. That's what is pointing me to module. Any help would be appreciated.

Thanks in advance, Chris

Side note. The first gauges I installed were the tachs, two weeks ago. Boat ran fine and the tachs worked properly.

Resist the MSD urge.

Since both died at same time:
1st: think / remember how the engines are tied into each other electrically.

Don’t let your brain get a head of you and just systematically ck voltage from battery to ignition switch and back. A volt meter and test light are your best friends here.

will it crank over

As far as ignitions themselves:
Do you have tbolt iv ignitions ?

Yes it cranks. After it quit, I checked voltage at the coil + with key in the run position. No power, checked with meter and test light. I will have to dig into it tomorrow. Spent the afternoon after work wiring in new gauges. Ran out of daylight, and energy. I think it's clear I missed something as far as both systems being connected. Just not sure where to look. What's the correct way to tie them back in? If that's an option or even the right thing to do. Is there a way to separate them and have them run individually? Thank you guys for the quick response, It is much appreciated.

As far as MSD, I've had good luck in the past. But, I'm open to other suggestions.

Thanks again, Chris

Fyi: the purple +12v wire powering each coil comes right from your cannon plug. From the beginning of the purple is…The ignition switch , then your lanyard kill then to your cannon plug.

So, since you messed with dash, ck power at ignition switch purple with key on run , if power t then lanyard in/out then to cannon….if no power at purple ignition ck battery power into ignition switch.

Will do. Tomorrow after work. Seriously, thank you.

do we know what the engines are.......

Original 330 hp 454s