2004 Yamaha 40hp Electrical Issue Burnt No Power

"I have a 2004 Yamaha 40hp 4 S

"I have a 2004 Yamaha 40hp 4 Stroke. I recently added a Perko switch and 2 batteries. I have the engines positive to the common on the Perko and the engines negative to one of the batteries neg terminals. The batteries each have a pos lead going to one of the Perko terminals 1&2.

I took the boat out today, it started up but was running a bit rough. It stalled out quite a few times but started back up until the last time when everything went dead. No tilt/trim and no starter. I pulled the cowling and there is a definate electrical burt smell coming from under the hood.

Any ideas what I did wrong or what has given up the ghost under the cowling?

Thanks for any advice.

Chris"

"Update, the CDI is melted in

"Update, the CDI is melted in the back and some of the wires going to the flywheel are also dark where they connect to the wires from under the flywheel. Do you think the damage is greater than the CDI. Also, ANY idea where I went worng with the wiring mentioned above? What did I do, I certainly dont want to burn up a new one. Thanks"

The only thing that comes to m

The only thing that comes to mind is that you have wired them up to produce 24 volts. Check to see what voltage is at the motor end of the main harness at the starter relays.

"Thanks Rollie,

I checked t

"Thanks Rollie,

I checked through all of the wiring and all seems correct. Is there any other reason a CDI would go up in smoke? Even now, with the engine disconnected from the battery and me pull starting it, the CDI continues to smoke and ooze goo down the side of the block. Just wondering if there is another issue besides a "bad" CDI. ?????"

you have a bad connection!!!

you have a bad connection!!!

"I looked over the wiring agai

"I looked over the wiring again and see that one of the battery cables coming from the pos post on bat 1 to the Perko is not of the same quality as the others. Looks like a weak gauge of metal and all of the wires to the cable are not even clamped into the terminal, maybe 1/2 of the wires are. Could this be the "bad connection" or am I looking for something more in line with a short?"

yep

yep

"Chris, for what it's wort

"Chris, for what it's worth, I just had a similar problem in the identical motor. My battery connections, which has wing nut connectors at the posts, were not as tight as they should have been. Even after cleaning the wire connections, I still had problems with cranking etc. I used pliers to really tighten them, which is an absolute must with wing nuts. If this connection to the battery is not perfect you get a tremendous amt of resistance and you will cook the starter and other things downstream . I'm done with wingnut batteries and only use the 1/4" stud types.Either way , it definitely is an improper connection somewhere. Just-in-time is correct!"