Engine swap help needed

bkm48198

Member
Joined
Nov 5, 2012
Threads
8
Messages
27
My Craftsman mower had a 13HP Briggs 28m707 motor and I have a briggs 310707 17hp motor I would like to put on it, the old motor blew up and oil poured from it so there is no fixing it. The wiring is similar but different, can someone tell me what wires need to be hooked up so it can run and also can I swap the carb from the old motor onto the larger motor? The 17 HP motor seems to have carb problems as the fuel will fill the cyld. quickly after cranking the motor over ...I had to remove the plug and crank the motor to empty the gas. I am used to working on V8 motors but have never worked on the small engine's like these...Thanks for any help.
 

Rivets

Lawn Royalty
Joined
Mar 11, 2012
Threads
59
Messages
15,305

bkm48198

Member
Joined
Nov 5, 2012
Threads
8
Messages
27
I hooked up the red and orange wires and got the motor to fire, there are a pair of wires going to the carb , one grey and one black, and I don't know what to connect to these wires. I haven't swapped out the carbs yet, maybe if these wires get connected the carb on the motor might work properly...any idea what they connect to?
 

scott47429

Well-Known Member
Joined
May 29, 2012
Threads
22
Messages
646
the gray wire should be the hot wire so it would need to go to a power source when the key is in the on position and the crank position the back one should be a ground to the frame or engine since the mower wasn't set up for this type of carb you will more then likely have to run new wires but shouldn't be a big problem good luck
 

Rivets

Lawn Royalty
Joined
Mar 11, 2012
Threads
59
Messages
15,305
I've got about 45 minutes, if you have some time. Where did you hook the red and orange wires? Where do the black and grey wire lead to? You said fired, but no running? Your my eyes now, tell me what I'm looking at, both engine and tractor.
 

bkm48198

Member
Joined
Nov 5, 2012
Threads
8
Messages
27
Red & Orange wires from tractor wiring hooked to red and orange wires on motor, black and grey go to the bottom of the carb? It's not running because if I connect the fuel line it pours straight into the cyld and hydrolics the cyld so the motor won't turn over until I take the spark plug out and blow the gas out of the motor. Both tractors were craftsman and both motors are B&S... one 13 and one 17 hp.
 

bkm48198

Member
Joined
Nov 5, 2012
Threads
8
Messages
27
the gray wire should be the hot wire so it would need to go to a power source when the key is in the on position and the crank position the back one should be a ground to the frame or engine since the mower wasn't set up for this type of carb you will more then likely have to run new wires but shouldn't be a big problem good luck

Thanks, I wasn't 100 % sure about the grey wire but assumed it needed to be hot while running, I'll try running a wire to it and see it it helps , if not I'll swap carbs out. The 17HP motor did have a fuel shut-off valve in the fuel line before the carb, I don't have that but I might get one.
 
Top