No spark from good 12v coil

This is a straight 12v positive ground system on 550 Cockshutt.
I've also swapped in a known good coil from another 12v tractor and same results. Could this mean a faulty wire from coil to distributor case? Could it be a condenser problem?
Thanks

Yes, yes and yes, points and ignition switch, too.

Just mentioned this lately on the fergie or Massey forum, but my Cockshutt 540 would not get a spark to save my/its? life. So a forklift guy down the road from me tried something he learned from an oldtimer. As I pressed the starter button, he had one wire off the plug and held it straight up, then slowly lowered it towards the plug as I was cranking it. About 7 or 8 inches away, there was a long blue lightening bolt spark, she started running on 3, he told me to shut it off, he reinstalled the plug wire tight on, hit the button again, she started like nothing was ever wrong, and has been fine since. Something about 'charging the coil'. Never heard of that before, but I will always remember this ol indian trick.

If you work through my Troubleshooting Procedure it should find the cause of no spark..

John T
John Ts troubleshooting

Man! I have heard everything now.
Walt

check to see if points are opening when the motor is turned over, if they are check the terminal ends that are used to connect the coil and condenser to the points some will rotate enough to contact the points mounting plate shorting them out,burnt points, bad condenser , bad points ground and on some models there's a small ground strap from the points to the dist. that may not have a good ground,a test light will help greatly in finding your problem, remove dist.cap with ign off turn engine enough to open points ,with the light wire connected to a grd.turn ign switch on and check for voltage on the switch side of coil if it doesn't have voltage disconnect the switch wire test it for voltage,if not problem is in the switch wire circuit,if it does connect it back to the coil,check the dist. side post of coil it should have voltage if so test the wires at the points, if there's voltage at the points check at the points arm, if so check for (bad points contacts) or points grd, if dist. side did not have voltage turn ign.off remove the wire turn ign. back on and test coil post it should have voltage if coil is good,if it has voltage turn off ign, replace wire remove the wire from points,turn ign.back on check wire for voltage at the wire terminal end that was disconnected from points, if it has no voltage it's shorted out,if it has voltage the condenser or points are shorted out

Best and easiest way to check for power is a test lite. Make sure you're getting power down to the coil first before anything else.

just out of courisoty under conditions how much voltage would it take to jump an 8 inch air gap

Simple take a test light or multimeter check for voltage at the battery side of coil. If non check switch. If voltage then open distributor remove coil wire from center of cap hold it near ground. Now open and close points with a screwdriver that has a good plastic handle. If they are closed then short across then if closed the just push them open and closed a few times. You should get spark from center wire from coil if not check coil.
Since you have already changed the coil I would look for voltage going in and the do other test. If spark when points are shorted coil is goo and you have voltage. Then replace points and condenser they are most likely your problem.
Walt

us ole indians know them tricks---mite-help-, 1942 model cherokee--lol--

Man how hard is it. I know I have posted this time and time again. A coil can not and will not work if the points do not work. The points are a simple make and break sort of switch. If that switch does not work you have no spark. When I go to check a tractor the first thing I do it pop the cap off the distributor the the rotor and dust cover. I then turn it on and open and close the points by hand. No spark at the points means they need cleaned I fix so many simple problems that way and have done I bet 500 of them in the past 20 plus years and that is a simple thing

Thats a tall one.Must have been one of those 40,000 volt coils.

My post was intented for the original poster, who has the same engine and problem mine had.
Yeah I know, but if I wanted to tell tall tales there's a diffrerent forum for that. All the big shot tractor experts couldn't help, but this is how a low tech non tractor expert helped me get it going, he tried to explain it to me like I am trying to explain it here, sorry but I don't feel like researching the impossible sounding theories, but a Massey guy did the same thing awhile ago, so he knows what I am on about. Far as I am concerned, if it helps someone by trying it- which is free, great. For those that want to laugh at me or the idea that worked for me an others, they can sit there with text books and instuments and analize their piece of junk forever for all I care.

(quoted from post at 21:03:39 09/12/12) just out of courisoty under conditions how much voltage would it take to jump an 8 inch air gap

Click to expand...

n free air, the generally accepted number is 25,000 to 30,000 volts per inch. Variables are always a factor, such as altitude, humidity, how sharp or rounded are the electrodes, phase of moon(?), etc.

8 X 25,000v = 200,000v

I have worked with high voltage for many years.25,000 volts is nasty.It can jump 2 inch gaps and crack glass.10,000 volts can jump a 1/2 gap.My 640 tractor ignition can jump a 1/2 inch gap with ease when the engine is running.7to 8 inches is a damn lie

I would not want to hold on to an ignition wire that would provide a 7 to 8 inch spark.