1995 OMC 5.0L Electrical mishap

[ggundersen3]

I had an electrical mishap yesterday on my 1995 OMC 5.0L. The boat had been winterized with the battery disconnected and removed. I wanted to reconnect the battery to work on installing a new radio/stereo. I made an embarrassing blunder and connected the battery in reverse. Yes! Positive on negative terminal and negative on positive. It sparked pretty intense the second I touched the cable to the terminal so I knew right away something was wrong so I immediately removed the cable from the terminal! It was only connected this way for maybe 1or 2 seconds at the most. I then connected the cables to the terminals correctly and tried a few things to see what may have blown. All accessories seem to work normal (lights, horn, blower), trim and tilt work normal. I tried cranking the starter and it cranked like normal. I didn't start the engine though. Is there a chance I didn't hurt anything because it was only connected in reverse for a second or 2? Is there a fuse or circuit breaker to protect in case this happens? If not, what could I have damaged and what can I do to check things out? Thanks! Been boating since 1963 and can't believe I did this. Help/advice appreciated here.

 

[Bt Doctur]

If you have electronic ign system, it could have blown
Do you have 12v at the + side of the coil?
Do you have spark?

 

[Grub54891]

What BT said. For a force that is invisible, it can sure make ya jump when you turn it Into lightning !

 

[Scott Danforth]

May have taken out the diode pack in the alternator

 

[Lou C]

Probably won't know for sure until you run it in the spring. I hope you didn't blow the module in the electronic distributor because those I don't think are still available (Prestolite BID system, same thing used on V/Ps of the same era). I guess you could replace that with a Petronix or the whole distributor with a Delco EST but that's a bit of cash. What I do when I buy a new battery...take a piece of duct tape and a sharpie and put the tape next to the positive post with a big + sign on the tape with the date the battery was installed. In the future this can help prevent those mishaps. The duct tape on this one was a pinkish/purple but you can see what I'm taking about...

 

[Bt Doctur]

could also spray the + battery post with red paint

 

[Scott Danforth]

Or clip the lines to the boat so they only reach the correct posts

 

[ggundersen3]

Thanks for the ideas. Here's what i'm thinking of doing to see what I'm dealing with. Let me know your thoughts. We currently are getting temps in the 20's deg F at night and 30s during the day with no snow so far. The boat is stored in an inside unheated storage facility that I have easy access to. But I'd have to pull it outside to do this. I'm thinking of buying another case(6 gallons) of -100 AF, filling my flush tank with the -100 AF, hook up the flush attachment (earmuffs) and try starting it. That way if it starts and runs, it's probably ok and undamaged and i'm not pumping any fresh water into it, only -100AF. I wont run it very long if it starts.
If it will crank but not start, then I know its damaged and I have to proceed diagnosing from there.

 

[Scott Danforth]

If you had your drive off, I would say just fire it for a second or two

or simply pull the impeller and fire it for a second or two. pulling the impeller on a cobra is much easier than on an Alpha or stringer

 

[Horigan]

Being a '95 he probably has a Cobra SX (Volvo) with engine mounted raw water pump. I'd just fire it up for a few seconds to confirm it starts, with the drive down to be easy on the U-joints.

 

[ggundersen3]

Here's an update. Whew! So good news! I did exactly what I said. Pulled it outside, lowered the drive down, connected the tank with -100AF, cranked the starter and it turned over and started. I ran it for a short period of time and shut her off. Seems ok. No apparent damage. Thanks for ALL your help, ideas and input everyone! And Horigan you are correct it's a '95 Four Winns with an OMC 5.0L with a Volvo Penta Cobra SX drive. Lesson learned here about being extra careful connecting battery cables.

 

[Lou C]

Good for you glad there was no damage! Now get some duct tape and a sharpie and mark your + battery terminal!