Briggs engine swap wiring help needed

twinfords

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I have a question regarding swaping Briggs engines, Blown engine is a 18.5 HP OHV intek single cylinder 31P777 0602-E2 in a Craftsman tractor #917.276761, the engine going in as a replacement is a 19HP twin cylinder Briggs # 42E707 2631 E1 from a Craftsman 917.270781 tractor. the wiring is different and i need to know what goes to what? the new engine only has 3 wire plug (manual choke) wires are red, orange and black. the tractor has a 4 wire with an additional red jumper (electric choke) orange, white, blue, black with white tracer, and the red jumper wire. can someone tell me what wire needs to go to what wire and what gets eliminated? enginewire.jpg

the attachement is on the mower side and the engine has only orange, red and black wires.
 

Rivets

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Had some time yesterday and did some checking. Both your engines run a dual circuit alternator which is good. You are going to have to do some checking, which wire goes where, but you should be able to swap the engines. You said that the newer engine had a three wire connector. One wire will be your kill wire coming from the coil. One wire will be your charging wire coming from the stator. The last wire wire be AC wire for your lights. If I had to guess, and it's only a guess, orange=kill, red=charging, and black=lights. You will have to trace. On the four wire connector on the tractor, you will have to trace where each wire goes to find where each engine wire needs to be connected. Kill wire should end up at the key switch. Charging wire at either the battery or solenoid. Light wire at the lights. Colors of the wires will change from unit to unit and engine to engine, so never assume red to red, orange to orange, etc. Please post where the extra wires go, so we can figure out what to do with them. This is going to take time and patience, so go slow and do one at a time. Best tools to use are a test light, VOM meter, and power probe if you have them. Remember that wires may not go dirrectly to the components and may be hooked to other parts through splices or connections. Good luck.
 

twinfords

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Thank you both for responding, i will be tackling this over the weekend, i will spend the time to trace the wiring and let you guys know what I come up with. I think the big issue is being able to turn the engine off once it starts or identifying the safety feature wires.

thanks Twinfords
 

twinfords

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hello guys, got slammed by the big storm so this project has been postponed.
 
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