No power past the coil on 8N

My 52' 8N suddenly lost spark to the points while driving. I have power from the ignition switch to the neg side of coil but nothing on positive side of the coil and to the points. I tested for continuity across the coil and its good. I replaced the coil with a spare and have the same result. I'm stumped!
 
Look for a short in the distributor. You have power to the coil and it has continuity so
there has to be something shorting out, stuck points, bad condensor, or more likely a wire
with no insulation or the block where the wire connects to the distributor.
 
With the points open check for power at the point side of the coil. If no power then take the wire off the coil and check again. If you have power with the wire off then you have a short some place in the distributor. One of the common places for a short is the insulator going threw the side of the distributor. If you have an ohm meter you can remove the wire form the point or the copper strip which ever it has and check to make sure the insulator wire if not shorted out
 
With the points open check for power at the point side of the coil. If no power then take the wire off the coil and check again. If you have power with the wire off then you have a short some place in the distributor. One of the common places for a short is the insulator going threw the side of the distributor. If you have an ohm meter you can remove the wire form the point or the copper strip which ever it has and check to make sure the insulator wire if not shorted out. My 841 had that problem years ago and now instead of the insulator it has a wire in its place and has silicone filling the hole holding it in place
 
Changed out point/condenser on my 50N Wouldn't fire a lick. Checked voltages. Once I found out how stupid I was because I put the wire on the wrong side of that backlite thing and it created a ground so I put it in right place and became smart again. Guess ill be smart till the next dumb move. Probably wont be long.
 
6 volt or 12 volt?

" I replaced the coil with a spare and have the same result. "

That's because there was nothing wrong with the coil.

The problem is in the distributor.

Do you have battery voltage across the points when they are open? Verify the gap on the points at .025. Then, dress the points by running a piece of card stock or brown paper bag through them. New points sometimes have an anti-corrosive dielectric coating on them & old points can corrode or pick up grease from a dirty feeler gauge or excessive cam lubricant. (I always spray my feeler guage blade off w/ contact cleaner.) Make sure you have voltage across the points, as in past the insulator on the side of the distributor. That is a very common failure point on sidemounts, along w/ the attached copper strip. It's hard to find a short there because it is usually an intermittent . So 'wiggle' the insulator & the copper strip a bit when you are doing your checking. If you find the short there, the Master Parts catalog lists everything you need on page 154. You can make the strip and you could also make the insulators as well. But, somethings are just easier & in the long run cheaper to buy. Get the strip, 12209, screw 350032-S, 12233 bushing & 12234 insulator & just replace it all. If you just replaced the rotor & lost spark, put the old one back in. Insure that the rotor fits firmly on the shaft & that the little clip is there. Make sure the distributor cap is not cracked & doesn't have carbon tracks. Check continuity on the secondary coil wire. Make sure it is firmly seated in both the cap & the coil. In fact, replace it temporarily w/ a plug wire. Next, remove the secondary coil wire from the center of the distributor cap, turn the key on & crank the engine while holding the end of the wire 1/4" from a rust & paint free spot on the engine. You should see & hear a nice blue/white spark. If not, you have a bad coil or condenser. Just put the old condenser back in to eliminate that as a possibility.

Post back w/ results; I'll be interested in what the problem was.
75 Tips
 
Thanks everyone for your help and advice. Here is what I did to get my 8N 6 volt tractor running.
-replaced condenser. No change, no power to points
-Cleaned the insulator, bolt, copper strip (and points). No change, no power to points
-ran a wire from coil directly to points. Success! I have power.
-cleaned plugs and checked for spark. I'm getting hopeful now...
-removed carb, drained gas, re installed.
-tractor started within 30 seconds even with the temperature at 7 degrees in the shop. I wonder why nothing ever breaks when it
it's 70 degrees and sunny?
 

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