115 merc cdi switch box issues

I recently bought a used Cdi switch box for my 1970 115 mercury. I installed it per the installation guide online. Once I had it all together I preceded to put some fresh fuel in and try.to fire it up on the hose. It started easier than ever before. I was going to take it out today so I hooked to the hose and.made sure.it was fire and run before hauling it to the lake and it wouldn't start. So I got to looking at it and noticed that it was arcing from the coil to the front plate where the unit mounts to. It also seemed jump from the coil to the terminal where the lead from the switch box tells.the cool to.fire. I.since put a larger deeper boot.on the.high.tension lead on the.cool. I also notice.the.screws that hold the cool to the mounting plate were loose and.i.thought that might have cause.the arcing since the coil gets it's ground from the screw on the mounting plate. Now I am not getting any.spark and I hope I didn't burn up the Cdi box when it arc ed to the switch box. It also sounds like a pop when I turn on and off the key. Any ideas on what to do would be great. Thanks John

Re: 115 merc cdi switch box issues

You probably damaged at lest one box maybe both, do a test on the system, they were not intended to hold up to 30000 volts

Re: 115 merc cdi switch box issues

Ok after a little more time messing it I have made a discovery. I've pulled the coil of my 114-2986 Cdi unit I notice a crack on the back side that faced the switch box where I couldn't see it while attached to the plate. it is right next to where the ground connects to the coil. IM assuming this happened because the nut that was supposed to be the ground path was loose so it made it's own
Way by cracking the insulation. Now I tested the brown wire on the trigger with the key on and still get 12v dc. The troubleshooting guide on the cdi website also said the wire going to the coil should read 200v dc with the key on. My analog meter went below the scale with the red lead to the coil wire and the black to ground, but when I switched the leads the other way it showed the correct 200v. Does this mean the capacitor has reversed polarity or is that normal. IM hoping that if I can find a replacement coil it will all work again. Can anyone tell me what coil I can replace the bad one with. There's no numbers I see on just the coil it comes as a switch box coil set new. I've seen they sell just a coil same size and design for Johnson Cdi ignitions so I hope they have one for mercury. Should I be worried about it reading reverse polarity on the lead going to the coil? Any help would be great.

Re: 115 merc cdi switch box issues

That's not a coil it's a transformer so polarity should not matter, if the box is not fried.