68' Mercury 35 hp with no spark on #2 sparkplug

Hi everyone! I recently bought a 68' Mercury 35hp 350 motor (serial # 2301754) that was only running on one cylinder when I got it. I replaced the points, checked the gap, condensors, and replaced the #2 ignition coil that was cracked. Unfortunantly, the motor still ran on only the #1 cylinder. Tried 3 other sparkplugs, but still no fire coming from #2. Even with a new sparkplug hooked to the sparkplug wire and the motor fired up (with the plug out of the motor), it still won't spark, so it's not flooding out or anything. I'm begining to question the connection between the sparkplug wire and the new ignition coil. The ignition coil has a hole with what appears to be a small pin inside of it. My sparkplug wire had no connector at all on the end and I assumed that the end of the wire simply pressed into the hole of the coil to contact with the pin inside. Was this plug wire suposed to have a connector of some kind that I don't have? If so, I need to know what it is and where to get it. Thanks in advance.

Re: 68' Mercury 35 hp with no spark on #2 sparkplug

Make sure the wires on the point stud are not grounded and the kill wire for that cyl is on the right screw on the junction box on the side of the engine 2 of the screws attach the block to the engine and would ground the cyl out. Also the plug wire can short out to the bottom of the stator. You can check the point side with a ohm meter to see if the points are functioning of shorted and with the points blocked open you can check the secondary coil wire for a direct short but a arc will not show up with a meter.

Re: 68' Mercury 35 hp with no spark on #2 sparkplug

Thanks for the reply Laddies!! All I have to work with here is a light tester, but I've found some things that are hopefully helpful. The 2 end screws on the Juction block are not connected to any wires (which is good). With the key on, I have light on only one of the two "coil/points" wires at the junction block. I took the screws out of the junction block and tested the wires coming from the harness (without them being connected to the coil/points). Same thing- Only light on one of the two wires. I then unhooked the main harness cable and tested the socket on the "Boat End"- Have light on the main battery cable to starter, the starter soliniod (when cranked over) and only one other socket hole (which is probably the coil/point that is getting fire). I thought about connecting both coil/point wires to just the one wire that is getting fire to see what would happen, but was afraid it might damage something or cause both cylinders to fire at the same time. One other thing that just occured to me as I think about it. The motor that I used on this boat before was a 40hp Mercury with electronic ignition. When the motor died, I bought this 35hp Mercury with points ignition. I didn't get a harness or controls with it, so I used what I had. It plugged right up to the new motor, so I assumed it was the same. Maybe not?

Re: 68' Mercury 35 hp with no spark on #2 sparkplug

Wish I could understand your test a little better but can't so maybe this will help. As near as I know a test light will test any cicurt with voltage in it. The problem is if your magneto system has any voltage going to it from the battery or what every it will burn the magneto up. When testing your magneto the points for 1 cyl will always be closed so 1 of the 2 wire to the lgn. switch will always show a short,, thats why you need to block the points open. If the wiring harness you are using is for a battery ign. system and you have voltage going to 1 side of the magneto you will need to change the switch.