bmwford94 0 #1 Posted September 7, 2011 I bought a tecumseh hm-80 awhile back from one of my friends. The engine is an 8hp pull start with the option of key start. He gave me a new starter for on it since the old one was bad, now the trouble is how to get it wired into the tractor i have. I have a 1973 8hp 4sp. Please help i would like to get this finished for winter so i dont have to pull start it . Share this post Link to post Share on other sites
JUSS10 250 #2 Posted September 7, 2011 what model tractor do you have exactly? your best bet would be to find the wiring schematic for that tractor then find the wiring schematic for the new motor. hook up the starter lead and figure out the charging system. sorry this is vague but without know what sort of charging system the tecumseh has its tough to say "hook this wire to that wire" Share this post Link to post Share on other sites
JUSS10 250 #3 Posted September 7, 2011 hmm sorry about that, i didn't know a 8hp 4 speed was an actual tractor name... so thats the tractor. below is the wiring schematic i pulled from a manual that was sourced for your machine. the black circle is showing the heavy gauge wire that goes to the starter from the solenoid. that should be a direct swap. next is the charging system. not knowing how the charging system on the hm80 works i circled both the AC leads and the DC lead. if the new motor doesn't have a rectifier/regulator built in, you will need to find the AC lines that come from the motor (usually yellow or black) and those will go into the regulator/rectifier thats already on the tractor. if the new engine has a rectifier/regulator on it, you just need to find the charging lead and replace that with the orange wire that is circled with the orange wire on the schematic below. finally there is the ignition system. not knowing what style ignition the tecumseh has its tough to tell you what to do there. if its like any techy motors i have worked on there should be a "kill switch" wire coming from it. this is usually just grounded to kill the engine. not sure if thats how the current ignition worked but if so, you can just take the black wire that runs up the left side of the diagram that goes to the coil and connect that to the kill wire on the tecumseh. once again, not sure if thats how your ignition system works or will work with this new engine but hopefully this at least gives a starting place Justin Share this post Link to post Share on other sites
bmwford94 0 #4 Posted September 8, 2011 Ok, maybe if I told you what I have yet of the tractor... Well, I still have the basic frame and all the wiring harness that would get plugged into the key, but I dont have the volts meter, or a starter generator. The engine I have has the starter built onto it, but no wires on it anywhere as if it were never hooked up before. I am probably just going to take it to the local wheelhorse guy to see what he can tell me since he sold me the engine and extra starter. i thankk you for your attempt in helping me out, who knows maybe the diagram will help me. Thanks!! Share this post Link to post Share on other sites
