Old Merc

Hey.<br /> I have an old mercury That lost ignition... is there supposted to be power going to the magneto when the key is on or is that wire to shut it off??

Re: Old Merc

That is probably just a kill wire that grounds the coil.

Re: Old Merc

if thats a kill wire how do i test the coil beacuse i lost spark!! Im a Johnny/Rude guy.. not a merc fan

Re: Old Merc

Don't worry, I can speak fluent JohnRude! Just think of it as an old Seahorse V4 with Magneto Ignition. Operates on the same principle. If you suspect there may be a problem in the kill wire circuitry, you can disconnect it from the mag and test it with a meter. With the key 'off' you'll have continuity thru the wire to ground, and with the key 'on' it'll have infinite resistance.<br /><br />Most likely the points are dirty. If cleaning the points to bare metal and gapping to .008"-010" If that doesn't do the trick, you may have to remove the coil and check for burnt marks. You can also go to the www.maxrules.com site and look up the tuning info for your particular model.<br /><br />HTH.......ed

Re: Old Merc

did i miss sumthin, what year and horsepower are we talking... i mean what is considered old?

Re: Old Merc

Howdy,<br /> Im back At my house now.. <br /> I took the magnetos all apart and cleaned all the connections, cleaned the points and regapped them, and took the coil out to have a look at it. the coil looked good not black marks. when i put it back together i had spark. than i didn't than i did!?!?!?! Whats causing that, The kill wire is unhooked during this testing.,<br /> Phat Mike It's a Old Merc. 1964 50hp Four Cylinder

Re: Old Merc

Originally posted by E120B:<br /> Howdy,<br /> Im back At my house now.. <br /> I took the magnetos all apart and cleaned all the connections, cleaned the points and regapped them, and took the coil out to have a look at it. the coil looked good not black marks. when i put it back together i had spark. than i didn't than i did!?!?!?! Whats causing that, The kill wire is unhooked during this testing.,<br /> Phat Mike It's a Old Merc. 1964 50hp Four Cylinder

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From experience with my '62 Model 400 45hp Four Cyl, where I had the same problem a couple years ago:<br /><br />Check the wire inside the magneto, especially the insulation over the wire. Mine was moving back and forth along the wire itself, so it would spark when I had the mag out and hooked it to a meter and played with it, but upon reassembly, the insulation would move and ground out the circuit.<br /><br />I replaced the wire with a new one and a chunk of wire and a bit of solder later, waalaaa, running motor.