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Chad, Until Bob M gets here per your request, I will say this is more of a place for a voltmeter or a cheap simple 12 volt indicator test lamp instead of that beeping continuity tester. You need a test lamp indicator at various locations such as the coils input (NOT to distributor) terminal and the starter solenoids lil S activation terminal to verify shes getting coil voltage when ON and solenoid voltage in the START position The coil is neverrrrr rr gonna fire until when you turn on the ignition switch theres hot voltage getting to the coils high input (NOT to distributor) terminal. You might wanna try n hot wire the coil with temporary jumper wire hot battery voltage to the coils input n see if she produces spark then in case the ignition switch or its circuit to the coil is bad (see below). NOTE if the problem is she seems to fire n run ONLY while the switch is in the START position but she stops firing when its released yet still in the ON position..... My guess would be theres a series external ballast resistor after the ignition switch and before the coil and its bad/open LOOK FOR AN EXTERNAL IGNITION BALLAST RESISTOR and verify it has continuity and measures around 1.5 to 2 ohms ????? ????? if its bad/open and the tractor has a solenoid with the extra lil I terminal wired to the coil that could accoutn for ehr to fire while crankign but not fire otherwise !!!!! !!!!! The ignition switches IGN output terminal ought to turn hot when in the start or run positions to feed voltage down to the coil (per above) and its starter or solenoid etc terminal ought to get hot when its held in the spring START position to send voltage down to the starter solenoids lil S activation terminal. Do I understand corrctly that you have determined theres no spark out of the coil is the problem or the starter motor wont crank when in the START switch position????? ????? If the problem is theres no spark, work through my Standard Troubleshooting procedure for Non Spark below and it will help find the problem like a bad ignitiion switch or coil or points etc..... ..... . If the problem is no cranking I gotta guess ???? it has as electrical starter solenoid switch so verify that and if it has a lil S activation terminal and if it turns hot when the switch is in the START position n post back your findings n questions..... ... Another unknown is it if uses an exterior series ballast resistor after the ignition switch and before the coil in which case it may also use a starter solenoid with an extra lil I terminal that feeds hot unballasted voltage to the coil ONLY while cranking. We gotta know the problem like no spark or no cranking before we can help you much further and Im in the dark sittin here concernign that particular tractor and that series coil wiring you mentioend about a fuel solenoid ?????// but regardless if its a coil ignition shes gotta have coil voltage when the switch is on to ever produce a spark. This may or may not help but if theres no spark it ought to help determine the cause. TROUBLESHOOTING A BATTERY POWERED EXTERNAL COIL TYPE IGNITION SYSTEM: PRELIMINARY CHECKS: (A) To see if it happens to be a cap n rotor problem and to see if at least the coil is firing, remove the coil wire from the distributor (leave coil end intact) and place its bare end to within 1/8 inch from tractor iron, turn her on n crank her over, and see if she jumps that gap with a good visible blue spark????? If so but the plug wire ends (from wire end to 1/8 inch to frame) or the plugs themselves don’t fire, its a cap n rotor or plug wire problem. If the coil wire isnt even sparking, see below. (B) Next open the cap and see that the points are gapped correct and indeed opening and closing as the engine is cranked and the distributor shaft rotates and MAKE SURE THEY ARE NOT BURNED OR PITTED OR CARBONED UP BADLY !!!!! !!!!! If so, running a point file between them to clean them up might make her run again HOWEVER that’s only a temporary cure, so if that cleaning makes her spark, INSTALL N GAP NEW POINTS. In the event they appear good but only gray oxide coated, non abrasively clean/buff/polish them using say a dollar bill or shop cloth etc. and see what happens. MORE TROUBLESHOOTING IF ALL THE ABOVE STILL FAILS TO MAKE HER SPARK 1) THE VERY FIRST THING YOU GOTTA HAVE is voltage to be present on the coils high supply (NOT to distributor) terminal when you turn the Ignition switch ON. If not she cant ever fire, but in the event the ignition switch or circuit/wire down to the coil or any Ballast Resistor is bad or open, you can HOT WIRE it by jumping a hot ungrounded battery voltage source to the coils high input supply (NOT to distributor) side n see if she runs then???? If she fires hot wired, you could have a bad ignition switch ((That can happen, when Ignition is on, the switches IGN terminal must turn hot)),,,,, ,or an open Ballast (if it has one) or a bad/open wire from switch to coil. If the switch is good, if you turn the ignition switch on and place a test lamp on the coils high (NOT to distributor) terminal SHE MUST LIGHT UP. If not again, look for an open Ballast Resistor (if it has one, it should read around 1.25 to 2 ohms across its terminals) or bad/open wires from the switches IGN output down to the Ballast (if it has one) and distributor. 2a) When the Ignition switch is turned on, voltage should appear on the coils high input side. That would be 6 volts on a straight 6 volt system or 12 volts on a 12 volt non external ballasted system, or around 6 volts on a 12 volt system that used a 6 volt coil plus an external Ballast Resistor and the coil is good and the points are closed and they and ALL wiring is good. 2b) To insure the coils low voltage primary winding is not bad/open, use an ohmmeter and measure its DC resistance between its lil + and -terminals. If its an open circuit (no continuity) its bad/open and will NOT work. It should measure around 1.25 to 2 ohms or so if its a 6 volt coil and maybe 2.5 to 3.5 if its a 12 volt internally ballasted coil. NOTE CAUTION have all leads and any voltage source DISCONNECTED FROM the coil for this simple primary winding continuity test. 3) Next, place your voltmeter or test lamp over on the coils other low to distributor terminal side, turn her on and crank the engine over. 4) A test lamp there should flash ON (when points are open) and OFF (when points are closed) as the engine is cranked slowly. 5a) If the lamp never comes on there, the coils primary is bad/open,,,,, ,,,,or the points are never opening,,,,, ,,,or theres a shorted/bad condensor (remove its lead to points and see if lamp comes on, if so, bad shorted condensor or its wiring),,,,, ,,or the points wire is shorted,,,,, ,,or the distributors side pass thru stud is grounded (use ohm meter to test that),,,,, ,,,or the points may have a shorted spring. 5b) If the lamp never goes off as engines cranked, the points are not closing or are bad,,,,, ,,or the wire or circuit is missing from the distributor to the points,,,,,or the distributors not well grounded to the tractor. She cant fire the coil unless its low side is getting a conductive ground return path via closed points and then the circuit is open when the points open. Be sure the condensor or its wiring is NOT shorted out and see if the lite comes on (when points open) with the condensor disconnected. If removing the condensor makes her spark, replace the condensor. SUMMARY Be sure the points are closing fully and open on high cam and ARE NOT BURNED OR PITTED OR CARBONED UP BADLY,,,,, ,theres voltage present on distributors high side at all times when ignitions on (or its a bad switch or open ballast or bad wiring to col),,,,, ,voltage on coils low side flashes on and off as distributor is cranked,,,,, ,,,condensors not bad/shorted,,,,, ,,no shorts in wires to points and no shorts in pass thru side out distributor stud,,,,, ,,coil has continuituy. You may luck out n just need a new set of points. If the coil wire fires (see above) and the plug wire ends to 1/8 from frame but NOT the plugs, they are baddddd ddddd . Check them BOTH. Good Luck n God Bless, post back any questions and your findings and any questions. John T Nordhoff in Indiana, retired electrical engineer who usually lurks over on the Mother Deere boards versus over here on the “dark side”.
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