Magnito Recharge?

Larry,
When mine does that, it usually means I need to replace the plugs. I'm not ruling out a weak coil, but the plugs may be fouled. Another trick is to get the wire so it leaves a small gap between the plug and it's self (not on all the way).
This will create a hotter spark, but makes the coil work harder. On a fouled plug it makes enough juice to jump the gap.
Matt

What/who's plugs are you using.

Why are you pulling the plugs to purge the cylinders....that's what the drain cocks (on the bottom) are for, otherwise it's still possible to have liquid fuel or oil laying in the bottom of the cylinder.

I have had plugs that fire fine out side the cylinder and when there is a little back pressure will not fire. Most the time it is one brand. You might want to try a different brand.
Terry

Just leaving one plug out doesn't help the mag/coil, it only could hurt it by building up a potential that isn't dissapated. Some of the Eisemann mags had a internal gap so the energy would be relieved if a plug wire came loose. I suppose todays better quality windings would lessen that trouble. Still, the thought that the coil would have enough to fire one but not both seems suspect. would a bad condenser do that? You didn't say what brand of mag you are using, AB, Wico, or Eisemann. In my experiance, the AB mags are almost foolproof.

I have found that Champion spark plugs, or any other plug with a cadmium plated base seem to foul much faster in the older low compression engines than plugs such as AC, Autolite or others with a Black Oxide finished base. I don't know why, but they last longer. I once had a 1937 John Deere B and those $9 apiece Champion W14's would last about 2 tractor shows before they fouled. I switched to AC plugs (same heat range as the W14) and they lasted a full summer of tractor shows and putting around the neighborhood.
If you are not getting spark from one side of your magneto, I'd check the cap inside for carbon tracks, could be shorting internally.

just a couple more thoughts , make sure the wire are real wire to the plugs and that they connect good at all places. magnetoes donot like carbon wire , then make sure the spark will jump 3/16 inch at crank speed, if not it will start hard at best, then use autolite plugs , the rest of the new ones are junk, nkg may also work. then if it has fuel and a little compression it will start on the first pull .Old rule is if coil fails it will fail when it is warmed up good, a condenser will somtimes start and run for a few seconds or only fire one time and not work any more , if in doubt replace it. hope this helps , ron meeder

What/who's plugs are you using.

Why are you pulling the plugs to purge the cylinders....that's what the drain cocks (on the bottom) are for, otherwise it's still possible to have liquid fuel or oil laying in the bottom of the cylinder.

[quote="Old Magnet"]What/who's plugs are you using.

Why are you pulling the plugs to purge the cylinders....that's what the drain cocks (on the bottom) are for, otherwise it's still possible to have liquid fuel or oil laying in the bottom of the cylinder.[/quote]

OM, Rookie at the wheel. I had the drain cocks open too but wanted to see if the plugs were soaked. While I had it out I turned over the motor to purge the cylinder. As it turned out, it's taken me down the path of the problem. Rookie luck.

Rig up a 6v battery test circuit light and leads. Touch one lead to the condenser metal jacket and the other to the center post. If the light gives a short flash it is ok. If it flickers its leaking. If the light stays on it's shorted.

If the coil fires one plug it's probably ok. Pretty rare to have them require remagnatizing. Can't be to bad if it has recently run.

I have had Champion plugs come dead as new. Also intermitent firing under load.
I use the NGK 6 or the Autolite 386.

Be sure the mag has a good ground.