new to horses 1 #1 Posted August 3, 2023 I've got a barn find 312-8 model 73363 that won't charge its battery. I got it running and operating as it should but jumping it every time I want to use it is getting old. I have found a wiring diagram for it and electrical is my downfall in all applications. Can someone explain to me in simple terms how I can bypass the wiring harness and directly wire the tractor to charge the battery? Thank you. 20230729_154406.mp4 1 Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,509 #2 Posted August 3, 2023 There is nothing to bypass. The regulator output goes to the Light terminal of the ignition switch so it is disconnected when the key is OFF. Did you look at the charge diagram on the downloaded file? You must download to see it. 2 Share this post Link to post Share on other sites
peter lena 8,085 #3 Posted August 3, 2023 @new to horses do you have a battery charger or a battery tender ? another glairing thing to me is the un clean engine , sold one of those that was packed behind the dash with damp rotted grass , another thing you can easily do is to use an alligator clip test wire , from the battery cable ground bolt to the RECTIFIER , bolts upper front side of engine cover , 3 prong plug in ,looks like an alumunum unit ,next to outside of carb , loosen the 2 bolts that hold it in place , get some dielectric on the bolt down points , just a little , also do the same on the removable wire plug in . move it around before tightening , to insure conductivity . when you restart , you could have charging . if its good and was only corrosion , easy . your battery should be in good charge rate . also check related fuses . done this on horses , first electrical charging issue , might have to replace rectifier , very easy . pete 1 Share this post Link to post Share on other sites
SylvanLakeWH 24,227 #4 Posted August 3, 2023 is battery good? Have it load tested. if yes, nothing to bypass to charge it and keep it on a battery tender. 1 Share this post Link to post Share on other sites
new to horses 1 #5 Posted August 3, 2023 2 hours ago, gwest_ca said: There is nothing to bypass. The regulator output goes to the Light terminal of the ignition switch so it is disconnected when the key is OFF. Did you look at the charge diagram on the downloaded file? You must download to see it. Could you link charge diagram please I can't find it. Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,509 #6 Posted August 3, 2023 Download this one 1 Share this post Link to post Share on other sites
gwest_ca-(File Mod) 10,509 #7 Posted August 3, 2023 If you need to dig deeper here is the engine service manual. It will walk you through charging system diagnosis. Something you don't understand by all means post your questions. 2 Share this post Link to post Share on other sites