# Wiring up new Briggs&Stratton engine 17.5 HP



## LTC (Jun 9, 2016)

I am trying to put a new engine on an old Craftsman mower for my dad. 

Craftsman Mower
917.256451

New Engine
31R907 0006 G1

Wires coming from the mower:
Red
Black
Orange

Wires coming from the new engine:
Red( alternator/regulator)
Black(magneto)
Grey(carburetor solenoid)

Any assistance would be greatly appreciated !


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## Bill Kapaun (May 8, 2007)

Connect the motor RED to tractor RED & ORANGE.
Orange is the lighting circuit. On the old engine, you had a separate AC output for that.
BLACK TO BLACK.

You'll need to connect the "L" terminal of the key switch to the fuel solenoid.
Look at the "truth table" on the lower left of the schematic.
The fuel solenoid will have power in the Run & Start positions, but NOT when Off.


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## Bill Kapaun (May 8, 2007)

BTW-
BLUE would be a preferred color for the fuel solenoid.
Don't use an existing color.
It'll be easier to sort things out down the road if electrical problems occur.


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## LTC (Jun 9, 2016)

Awesome! Thanks for your help Bill! I'll will do this when I get home from work this evening!


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## Bill Kapaun (May 8, 2007)

One caveat-
IF you leave the light switch ON, you'll run down the battery.
That wouldn't be the case with the old engine.
You might have to "train" dad.

Do you know if this is the 5 or 9 Amp system?
IF 5, you really won't have enough to operate lights, fuel solenoid and provide battery charging at the same time.


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## LTC (Jun 9, 2016)

I got it done tonight and it's running like a champ! 
Dropped it off at my Dads and explained leaving the light switch on will drain the battery while it's not running(I'm sure I'll have to go charge the battery once or twice before the lesson is learned lol). Thanks again for your assistance!

I'm not sure if it's the 5 or 9 Amp system, any clue as to how I'd find out?!


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## Bill Kapaun (May 8, 2007)

The only difference is the size of the flywheel magnets.
A bit of Google and-

https://www.amazon.com/Briggs-Strat...dp/B00IUAYEYU?ie=UTF8&*Version*=1&*entries*=0


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