Wisdom of experience needed

Working on a friend's tractor, I'm stumped by something that has to be utterly simple. New points/condenser installed in distributor. High voltage shoots out of the coil wire to frame just fine when
cranked over. But it's lost totally somewhere between there and the plugs. The plugs are new and correct, gaped correctly etc. The cap and rotor are new enough to show no wear on either and it was running
fine until it wasn't running at all. There are no visible problems with rotor or cap. The coil and plug wires appear in good condition and show minimal resistance on ohm meter. Coil wire definitely conducting OK. Somewhere between the hot end
of the coil wire and the plugs it's gone. Had good spark from plug wires, then nothing. What am I missing here in addition to my sanity??
 
I would try another condenser even if you just put a new one in. The same thing happened to me last year on my MT and drove me crazy. These new condensers are junk. Good Luck, Mark.
 
If theres good fire out of the coil and coil wire to ground but NOT out ANY of the dist caps plug wire terminals to the plugs, sounds like the cap and/or rotor is the problem even if they look good to the eye. I have seen rotor tips that lost the plastic insulation integrity so the spark shorted to the distributor shaft which kills any fire to the plugs......I have also seen the carbon in the caps top center go bad.......I have observed tiny carbon traces inside the caps............If timing was wayyyyyyy off the coil may be firing other then when the rotor tip is in line with the plug wire inner terminals but they will often spark over to the nearest terminal in that case,.

Id try a new cap n rotor tip

John T
 
Try replacing the rotor button with a known good one. I have one in my tool box to show people that ran one hour and then the tractor died. It looks like new but will not let spark go pasted it. So it has to be the rotor or the cap.
 
Take the distributor cap off and hold the coil wire close to the rotor. If it sparks to the rotor tab, you have a bad rotor.
 
(quoted from post at 18:30:01 09/06/17) Working on a friend's tractor, I'm stumped by something that has to be utterly simple. New points/condenser installed in distributor. High voltage shoots out of the coil wire to frame just fine when
cranked over. But it's lost totally somewhere between there and the plugs. The plugs are new and correct, gaped correctly etc. The cap and rotor are new enough to show no wear on either and it was running
fine until it wasn't running at all. There are no visible problems with rotor or cap. The coil and plug wires appear in good condition and show minimal resistance on ohm meter. Coil wire definitely conducting OK. Somewhere between the hot end
of the coil wire and the plugs it's gone. Had good spark from plug wires, then nothing. What am I missing here in addition to my sanity??
 
Sorry about that, first post on this site. This is going to sound really stupid but I chased this very same problem on my Massey 44 for about 3 weeks trying everything that made sense to no avail, then a guy came over to look at another tractor I had for sale. I took the battery out of the 44 and put it in that tractor and it wouldn't start, I grabbed another battery and it started. I put that battery in the 44 and it started. I don't know but the 44 has ran with that battery for the last 2 years.
 
I agree on cap and rotor. A brand new cap and rotor last year from tractor supply on a 8N and I was having the same issue. The tolerance on the manufacturing was way off and not getting power out of the cap. Got a set from my local Napa and it started right up.
 
Just had a problem with mine. When I would break the points with a screwdriver it had good spark. I put the cap back on and weak spark. Reset the points, someone stripped the adjuster screw, fired right up and ran better than before.
 

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