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Discussion Starter · #1 ·
I have this engine which was originally on a MTD or Murry Lawn tractor. I am intending to use it on a powered deck for on a ATV.

I am not familiar to much with the newer OHV engines per se, but my questions are:

What is the wire that goes to the carb flaot bowl for. Its a solenoid from what I figurerd out when I dissassembled the carb to clean it. Is it necessary for this engine to work, here in the south. Someone once told me IIRC it was an electric type choke for cold weather.

Now my other question is what are the two pairs of wires for that come out under the shroud. There is one pair of red and black and another pair of red and black, with the red wire on this pair haiiving what I assume to be the diode in the harness that would go to the charging circuit?

None of these wires are off the starter, 4 wires (2 pairs) come out from inside the engine.
 

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The one on the carb is an afterfire solenoid, it needs
voltage to keep the engine running. If you clip off
the needle's tip, you will bypass it.
Isolate the wires coming from under the cover,
2 from the alternator, and one from the coil's kill circuit.
Fish
 

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Discussion Starter · #3 ·
So what exactly is an "afterfire circuit" and do I need it? I understand you to say if I bypass it all I need to do is knock off the needles point, and it will work ok?

Ok 2 of the wires for the alternator, one for the kill system so whats the 4th wire for (1 pair of each red & black in a connector) 4 wires total? Would both alternator wires be red? or could it be a red and a black?
 

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Discussion Starter · #4 ·
Well in another (yes I have to admit I did also post my original question in another forum ) and getting abaout 5 different repl;ies to my original queston on wires in this engine, the scoop is like Fish stated.

One pair of wires is for the alternator + & - and this will have the diode in line with the positive lead.

The other two wires are: the red goes to the carb float bowl solenoid, and the black to the magneto kill.

The solenoid on this engine was leaking so I just substituted a 5/16" fine thread bolt with a nut to snug up against the float bowl. No more leaks.

But somewhere along the way during the wiring in of the key switch to have electric start, and battery charge capability, my buddy got his wires crossed and hooked up 12 volts to the magneto kill wire, and smoked it.............so now we need to find a new magneto coil assembly.
 

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Should be pretty easy to find. Check with any small engine repair parts store. They will usually have them in stock.
 

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I think you can probably find it online pretty easy if you got a part number. You can probably find the schematics online to figure out the part number too.
 

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Briggs puts out a pretty good small engine repair and maintenance manual. Its about $15. I have had it for a couple years and it is a good reference point for working on small engines. If I am ever stumped, I got it in the cabinet in my garage and most times, it helps me isolate problems. Great manual and it really isn't brand specific either.
 
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