I have a 540ci bullet engine and it's not firing. I've got 12v to the msd box and 12v to my ign switch but no 12v to the coil and I checked the power going into the msd box and it's good but no 12v power coming out to the coil. Could this be a bad msd box? It ran when I parked it but I had some issues with it not running right with fuel issues... Not that's solved and no fire! Please help!!! Thanks in advance!!

More than likely the MSD box. Buy a new one for a spare and try it. It if still dont work you have a spare box and if it does you found your problem. These things seem kinda unreliable in boats with the water and rough environment. Its always good to keep a spare one in your boat. Better to have an extra box on boat than getting towed in, but then again thats why I carry a spare engine

Check out the troubleshooting procedure at the MSD web site. Its pretty straightforward.

http://www.msdignition.com/page.aspx?id=3206

For what its worth, they do seem to be a bit problematic, and I now carry a spare as well.

ok I'll try it. I hope thats all it is. I didnt know these things were a popular item to carry extra on the boat... I guess I'll have to remove the weight in beer and carry an extra msd box. lol

msd stands for.... "marine stranding device" always guaranteed to leave you hanging some where.

Probably a stupid question but has anyone ever drilled a small weep hole in the MSD box to get rid of condensation? Might be worth a try

my coil. was bad on mine !!! my box is 20years old never fail me the coil goes and the pickup goes . the one thing is you have to keep your batterys at a full charge all the time for that to work good . on a stock setup the pick up always go bad i carry a spare in my formula

With everything hooked up as you have it, take a temporary jumper wire to give 12V to your coil. This may get it to fire. I've had many MSD 6AL boxes over the years and kinda assume it's gonne quit at some point so I always have a harness to trigger the coil right from the ignition module as a back up.

ON a few I've had I put two small vaccum fittings on either side of the MSD box. I hooked one fitting up to manifold vacuum and the other up to the air cleaner/flame arrestor. This keeps a steady flow of fresh air through the box. This is also common practice on LT1 engines for the opti-spark distributor.

You're not supposed to have 12 volt at the coil with an MSD,