Allis_HB112 Posted May 15, 2011 Posted May 15, 2011 I got to get this girl running, and the thing holding me up now is figuring out how to rewire the engine on this B&S 12 HP model #300421. Unfortunately I didn't take a pic of it when it came apart in pieces, and the wiring diagrams I have don't show anything about the engine wiring, other than part numbers. It appears there is a neutral stud next to the magneto, but other than the wire from the points going to it, where do ALL the other wires fasten? Am I correct in assuming there is a white wire going from the switch to the magneto? Does this need to be a heavy 12ga. wire? Where does the insulated magneto wire go to? Half of the wiring was junk, and I'm replacing what needs to be replaced. I can put up a pic if I need to. THANKS in advance for the help!
ReedS Posted May 15, 2011 Posted May 15, 2011 IIRC there are two wires on the mag coil, 1 wire (non-insulated) has a ring term, that attaches to the coil mounting bolt (ground), the other wire attaches to the stud. From the stud there should be another wire to the wiring block at the points cover, there are usually 3 wires at this point, 1 from the mag, 1 from the points, and the kill switch. The kill switch wire need not be heavy, 18 ga will do, just remeber that the kill switch circuit never, never ties into 12v +! If you hit 12v + with that circuit you've just fried your mag coil!
RayS Posted May 15, 2011 Posted May 15, 2011 The white wire is the kill wire. You hook it to the bakelite piece that the wires are fastened to in the 3rd picture. That bakelite piece fastenens to the point cover. I have also just hooked it up to one of the wires that come from behind the shroud. It doesn`t matter which one. The other goes to the points or in my case the Nova II ignition module. The white wire can be 12ga. - 14ga. or smaller there is no power there it just grounds out the mag.
Allis_HB112 Posted May 15, 2011 Author Posted May 15, 2011 Ray, I don't have a bakelite piece. I think my white wire came off the key switch and was connected directly to the stud with the 3 wires under the shroud. I have one end of a wire (2 pieces spliced together), with a small ring terminal on one end, and an empty splice on the other. I believe my white wire (which I no longer have) was the 3rd piece of that 3 piece wire. Does the bakelite piece serve any purpose other than connecting the white wire indirectly to the stud under the shroud (magneto wiring)? I want to run my white wire (16 ga.) directly to that stud. OK?
RayS Posted May 15, 2011 Posted May 15, 2011 The bakelite piece fastens to the top screw on the points cover. I don`t have the bakelite piece on my HB 212 either so I guess it isn`t a must. I wouldn`t hook it directly to that stud. I would use a wire terminal like this on the outside of the flywheel shroud. That way you could easily disconnect if you need to remove motor. They have them at TSC and Walmart.
Allis_HB112 Posted May 15, 2011 Author Posted May 15, 2011 I've hooked it directly for now. I'll add the connector when I'm done and determined the exact length I need of the white wire, as it's a foot or more too long right now. I have connectors similar to that I'll use. This is where I'm at right now: [img]http://i243.photobucket.com/albums/ff261/rocknss04/Allis%20Chalmers%20HB112/DSCF2144s.jpg[/img] [img]http://i243.photobucket.com/albums/ff261/rocknss04/Allis%20Chalmers%20HB112/DSCF2145s.jpg[/img] This shows the wiring to the switch, but also shows the accessory fuse panel I added for the new headlights, rear work light, and rear 12V plug for my 15 gal sprayer. [img]http://i243.photobucket.com/albums/ff261/rocknss04/Allis%20Chalmers%20HB112/DSCF2146s.jpg[/img] I had some help. That's Duke, our chocolate lab. He's almost 8. [img]http://i243.photobucket.com/albums/ff261/rocknss04/Allis%20Chalmers%20HB112/DSCF2147s.jpg[/img]
RayS Posted May 15, 2011 Posted May 15, 2011 Nice tractor and Lab. My chocolate is 3 years old now. Very smart dog.
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