Fordiesel69 263 #1 Posted April 19 Model: 72043 (264-H) Serial: 4901096 Tractor was purchases 8 yrs ago and the owner gave up as it was "totally dead". They were not wrong, it acts like there is no battery. I installed a known good battery and went over the ground connection as well as the main power feed wire. The only way to get it running is to disconnect the engine connector (to open the circuit to the magneto) and jump the starter. Runs like a champ. -I went over all the fuses and all test good with an ohm meter and they visually look good. -I found the red wire melted into the white wire on the ignition switch, and as a result it burnt the terminal clean off the ignition switch. (not sure why it didnt blow the fuses but at any case it is just the white wire going to the headlights. -I disconnected the ignition switch, and if you plug the engine connector back in, the mag get a ground and it stalls. (I dont understand this) -The prior owner bypassed the seat switch and his jumper is intact and tests fine. -I make sure the brake switch, and PTO switch were properly opening and closing. I am totally lost. It is 100% dead not one ounce of power. Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,047 #2 Posted April 19 Did you download the 7 page file? Each major circuit has it's own diagram which makes it easier to understand. 1 Share this post Link to post Share on other sites
Fordiesel69 263 #3 Posted April 19 Yes. Downloaded and printed it. But Im not sure where to begin. Again with the ign switch disconnected completely if you attempt to plug in the engine connector, it will stall. I could replace the igntion switch and solder and crimp in a new red but im not sure if that will resolve anything. Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,047 #4 Posted April 19 32 minutes ago, Fordiesel69 said: Again with the ign switch disconnected completely if you attempt to plug in the engine connector, it will stall. I could replace the igntion switch and solder and crimp in a new red but im not sure if that will resolve anything. That is the way it works. The ignition switch needs to power the kill relay for the ignition to work. The wiggly thing in the kill relay is a magnetic coil when powered. That pulls the relay towards the magnet opening the circuit that grounds the ignition to kill it. The NO contact in the relay is normally open. The NC contact in the relay is normally closed. Normally means the relay contact's condition when it is not powered. When like this the magneto is grounded so no ignition. 1 Share this post Link to post Share on other sites
Fordiesel69 263 #5 Posted April 19 So looking over the scehmatic i think i may be catching on....when the kill relay is relaxed "De-engergized" the contact is grounding the magneto wire killing the engine. So by me fixing the red wire it will "Energize" the kill relay and unground the magneto wire? 2 1 Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,047 #6 Posted April 19 Added more to my last post. You have it now. Keep us posted on your results. 1 Share this post Link to post Share on other sites
squonk 41,155 #7 Posted April 19 5 hours ago, Fordiesel69 said: Model: 72043 (264-H) Serial: 4901096 Tractor was purchases 8 yrs ago and the owner gave up as it was "totally dead". They were not wrong, it acts like there is no battery. -I went over all the fuses and all test good with an ohm meter and they visually look good. Did you actually have 12 volts through the fuse holder? Yes you checked the fuse, but where the wires attach to the prongs of the fuse holder is a weak spot and in the automotive world anyway are known to get a case of the green crusties. I would suspect one or both of the red wires coming out of the 30 A fuse holder is suspect. That would cause a No crank and no anything else because no battery power will get to the switch and to the small wire on the start solenoid. Also when jump starting the ignition won't work unless you unplug the engine connector because the kill relay is in the unpowered "relaxed and grounded position. 1 Share this post Link to post Share on other sites
Fordiesel69 263 #8 Posted April 22 (edited) SOLUTION / UPDATE -I replaced the burnt red wire and cut a slot in the melted ign switch connector to allow my terminal to fit. I then installed a new $17 ebay china ign switch. That fixed everything for one crank / start attempt! -I then was presented with a dead horse once again and it was indeed a poor fitment / connection on the fuse. Other than that it is fully up an running electrically. Thank you for the help. I was a bit lost at first of where to begin. PS - I would lover to know WHY the red wire melted at the ign switch, so much that it melted into the white headlight wire. Edited April 22 by Fordiesel69 2 Share this post Link to post Share on other sites
953 nut 55,321 #9 Posted April 22 3 minutes ago, Fordiesel69 said: I would lover to know WHY the red wire melted at the ign switch, so much that it melted into the white headlight wire. Edited just now by Fordiesel69 Probably a poor connection. Here is an explanation of the problems that can be caused by corrosion on electrical connections that was provided by @Save Old Iron years ago. The connectors used in this tractor series are in a harsh, corrosive environment caused by vapors from the battery being charged over a few decades.. Vibration causes the connections to loosen - corrosion starts within the metal terminals and a voltage drop develops across the corrosion. If you have a 10 amp current flowing across a 1 ohm resistance (contact corrosion) the electrical formula to calculate power is current squared times resistance so 10 amps x 10amps x 1 ohm resistance = 100 watts !! 100 watts of connector heating is the same as laying a 100 watt soldering iron on the connector Share this post Link to post Share on other sites
Handy Don 12,237 #10 Posted April 23 14 hours ago, 953 nut said: vapors from the battery being charged over a few decades I’m curious. Is anyone not running SLA batteries? And yes, I’m aware that SLA (sealed lead acid) batteries can vent if charged too quickly or if overcharged, but in normal operation they do not--the gasses re-combine in the internal electrolyte. And, FWIW, since the vented gasses represent a loss of oxygen and hydrogen from the electrolyte that cannot be replaced with new “distilled water”, the overall capacity of the battery degrades. Share this post Link to post Share on other sites
Fordiesel69 263 #11 Posted April 23 No. Cheap batteries last maybe 3 years somtimes 4 or 5 if you get lucky. An SLA battery is uber expensive and is good for about 3-5 years as well. Share this post Link to post Share on other sites
