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Help with wiring on sunstar

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I have an earlier sunstar (model 1691381, serial # 001829), 20 hp magnum. Anyone know where to find a wiring svchematic for this older model? I posted a link a coiuple of weeks ago to some wiring schematics but they are for later sunstars and are not the same. My woes are as follows:

I picked the tractor up last fall, not running. I rebuilt the engine and started it up 2 weeks ago. I didn't have it plugged into the harness. Engine ran fine. So hooked everything up. It turned over a few times with the key/ignition switch until the key went haywire and wasn't activating the start/run on the switch. Had my dad pick me up a switch at the simplicity dealer. They sold him a 6 prong MTD switch but the switch in it was 5 terminal originally. The 5 main terminals on the new switch are marked like the old one, B,S, G, L and M and are in the correct orientation. I don't know what the 6th terminal is for or if I can ignore it.  So my first question is, can a 6 terminal switch be used where it was originally as 5 terminal?

Next to my woes, I take the old switch out and I guess at some point the plug on the back of the switch had corroded or melted so it was removed and each wire was on the terminals separately with those slide on connectors. So I put them in the same position on the new switch. The engine cranked a few times, then nothing. I played around with the ground. I could get it to crank the odd time, next time nothing. The circuit breaker by the solenoid would get quite hot fairly quickly . So I'm trying to find a schematic to see if the wiring connectors  are on the correct terminals of the switch. Anyone know a link to an schematic for this earlier sunstar?

Next, just above the interlock module, there is a small square 9 prong plug that is mounted into the plate the interlock is mounted to. There are a number of wires running into the back of it but there is nothing plugged into the front of it. Doesn't look like there has been and I can find no harness anywhere with that type of plug to plug into it. Should something be plugged into it?

Also, is there supposed to be a fuse somewhere? I can find no fuse.

Lastly, just to verify, the wiring leading from the stator to the regulator, should the green wire be on the left terminal, the black in the middle and the white on the right terminal, looking at the terminal from the front?

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Yes Bill, thanks for the link. It helps a lot and I can now figure out the wiring. The old switch terminals were not marked except B for battery. Comparing the schematic, I see the terminal designations on the replacement switch are not in the same locations as the original switch. Also, according to the schematic, one terminal is for resistor or regulator. The replacement switch does not have an "R" marked terminal but instead has a ground terminal. So back to Simplicity to get the right switch.

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