JerryB 12 #1 Posted March 20, 2019 I can’t figure out why I have no spark. New plug and wire. Points are new. I just timed it also. My coil is also good too. Could it be my ignition switch. I don’t think they even make that switch anymore. If anyone could help I thank you in advance. Jerry Share this post Link to post Share on other sites
ebinmaine 62,332 #2 Posted March 20, 2019 Morning Jerry. We'd need a little more info to help you diagnose your tractor. Model, year to start. It could be a bad ground. Broken wire. You're already headed the right direction with what you've done. The ignition switch for that IS still available so no worries there either. (Most anything is around if you know where to find it.) Do you have a test light or DVOM? Share this post Link to post Share on other sites
Achto 26,182 #3 Posted March 20, 2019 Going on the premises that you have an automotive style coil, check to see if you have power to the + side of the coil when the key switch is on. There should be no power at this terminal when the switch is off. If this checks out then your key switch should be good. Another check here would be to ensure that the wire coming from the switch is indeed on the + side of the coil & that the wire from the points is on the - side of the coil. You mentioned that you installed new points. Take a dollar bill or piece of paper & run it through the points while they are closed, do this several times to ensure that the points contacts are clean. Also make sure that your points are opening & closing as they should.. 2 1 Share this post Link to post Share on other sites
The Tuul Crib 7,331 #4 Posted March 20, 2019 to did you replace the condenser as well? Share this post Link to post Share on other sites
wallfish 15,769 #5 Posted March 20, 2019 New points usually have a coating on them so always clean the contacts even when they're new out of the package. Small file is best. As stated above, must have 12v at the + side of the coil. Condenser and points connection to - side of coil. It will spark without a condenser or a bad one but will not run properly. No need to have the engine running to see a spark at the points. With the key in "run" and the points completely closed, flip the points open with a screwdriver and you should see a spark. That is, if everything else is good like all the parts, 12v at the + side of the coil, the contacts are clean and making contact, ground connection is good. Was this rewired or anything like that? More history and information will help with any internet diagnosis. 4 Share this post Link to post Share on other sites
squonk 38,559 #6 Posted March 20, 2019 You can take a 12 volt test light (available at any parts store & cheap) Clip the aligator clip to battery ground. Touch the + terminal on the coil with the switch on to verify power is getting to the coil. Touch the probe to the - terminal of the coil. Crank the engine with the starter and the light should flash on and off with the points opening and closing. If the light doesn't flash you won't get any high voltage out of the coil to create the spark. Recheck the points. 4 Share this post Link to post Share on other sites
roadapples 6,980 #7 Posted March 20, 2019 Check amp gauge contact's.. Share this post Link to post Share on other sites
JerryB 12 #8 Posted March 20, 2019 Thanks a million all of you guys. I really appreciate it. I’ll get back and let you know what I find out. Jerry 2 Share this post Link to post Share on other sites
JerryB 12 #9 Posted March 22, 2019 Hello again I’m almost sure I need a switch. I have a 1976 C81. Does anyone know what ignition switch I need. The one that is in my tractor is not the proper one and I want to get it back to original. thanks in advance Jerry Share this post Link to post Share on other sites
953 nut 50,997 #10 Posted March 22, 2019 103 990 is the ignition switch for a with battery ignition. 1 Share this post Link to post Share on other sites
JerryB 12 #11 Posted March 22, 2019 Thanks a million for that switch number. I appreciate it. Jerry 1 Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,440 #12 Posted March 22, 2019 More info on the 103990 switch. Click on the picture Garry 1 Share this post Link to post Share on other sites