Bill, I'm going to bore you to death ! ...smile.... Hope some of this will help !If you have cleaned and checked all the fuel filters and are sure that you have fuel to the carburetor then take a look at the ignition system. If it tries to start (fires some) when you crank the engine, then you probably have one of several problems…….Fuel system, weak coil, points not set right, bad condenser, bad spark plug wires to name a few. If it doesn’t even try to start, this should eliminate your spark plugs and spark plug wires. Pull the coil wire out of the distributor cap and hold it close to the engine block (bare metal) and see if you have spark when you crank the engine over. If you have spark, then the trouble might be corroded terminals in the distributor, bad rotor button, cracked distributor cap, moisture in the cap just to name a few. Since your engine was running fine before and suddenly stopped, it probably isn’t moisture or corroded terminals. If you don’t have any spark from the coil wire, then look to see if your points are opening or closing. The points have to open and close in order for the coil to spark. Take the distributor cap off and watch the points while someone cranks the engine. Another note about the coil…….even though you might have spark, the spark needs to be a blueish-white and not yellow. Now….lets assume that your points are opening and closing, but you still can’t get a spark from your coil. The next thing you need to do is check to make sure you are getting juice(voltage) from the ignition switch to the coil. To check this, you can get a piece of wire long enough to connect from the ungrounded side of your battery to the terminal on the coil (not the terminal that has a wire that goes to the distributor, but the other terminal. Now crank your engine to see if it will fire. If it fires, it is either your ignition switch or the wiring associated with this. Another note about the points……….normally, you will see a little spark when you crank the engine but it wont be a large spark. If you get a large sparking of the points, then your condenser might be the problem. Without going into great detail ….the coil produces a spark by the collapse of a magnetic field. The condenser is sort of an electric shock absorber that prevents the full spark from jumping back across the points when they open. If you see a “pretty healthy” spark across the point gap and no spark from the coil, then your condenser might be the problem. The reason that it is important to see a small spark on the points (assuming coil and wiring is good) is that if the condenser is “shorted”, then it basically eliminates the points and they can’t do their job. (kinda like wiring around the wall switch in your home, the light burns all the time, so the wall switch is useless…..in the case of ignition points, the coil fires at the second the switch is turned off and not when it is turned on.) Actually, the ignition system on one of these old tractors is pretty simple once you understand how everything is put together and how it operates. If you have spark from your coil and spark at the ends of your plug wires….and you know it is getting fuel, then the next step is to start looking at the timing of the spark.
The main thing to keep in mind is to eliminate possible problems systematically. Gary
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