Small Engines (Lawn Mowers, etc.): Wiring problems, briggs and stratton, briggs stratton

Question
I have a Murray riding lawn mower with a Briggs and Stratton 12hp engine model number 289707. The wiring was not connected when I purchased it (used). I need a diagram to show me how to install properly. It has an electric starter. My biggest problem is there is one red and one black wire coming out of the motor with no connectors. There is a black wire coming out of the front of the motor. I got the motor to turn over but it just cranks. But this only happens when I connect the starter straight up to the battery (it automatically tries to start without using the key). Can you help me please?

Answer
The wires coming out from under the flywheel should go to a connector on the engine side if you purchased this use somebody could have removed it or cut it.  The engine stator only produces AC current and you need DC current to charge your battery and run your accessories.  This is done by using a single diode in a system where there is only electric start battery charging and lights.  These wire is could also go to a bridge rectifier/regulator.  This is a switch with four diodes controlling the flow erection of the current.

You are correct You need a schematic.  I believe Murray is owned by Briggs & Stratton.  I suggest contacting outbreaks central distributor.  Look under gasoline engines in your Yellow Pages and normally the central distributor is listed separately.  Ask if they can tell you where you can purchase an owner's manual or service manual.

When you turn the key there should be a click letting you know the solenoid is operating.  This is how 12 V gets from the battery to the starter.  The smaller wires on the solenoid go through the safety system.  This includes the start and run circuit's.  The start circuit includes the seat switch, PTOs switch, break and or clutch switch, and the key switch.  The trickiest is the PTOs switch because it is a double pole double throw switch.  This means when this switch is turned on or off two things happen one is turning the electric clutch on and off and being sure you were in the seat.  Both sides of the switch have to operate.  Check every switch to be sure they are operational.

If you can find nothing on this engine attach a voltmeter to the wires coming from the engine start the engine and measure the voltage coming from the stator if it is DC voltage there is a diode already in the wiring if there is only AC it would go to a regulators/rectifier.  The trick is getting the engine to run.  Be sure you do not have fuel related auric ignition related problem with the engine.

This engine requires a battery is fully charged to start a fully charged battery for lawn and garden tractor measures 12.6 V.  A battery with less than 12.6 V will have a hard time starting the engine.  The reason a 12 V battery measures 12.6 V is that it has 6 plaits in the battery and each plate measures 2.2 V.  You could always try removing the spark plugs so the engine turns over briefly if you do this attached the spark plugs to the ends of the wires and prop them up away from the spark plug hole.  This will conserve your battery power because the engine is easier to turn.  Once you have it operating with the key switch put the plugs back in and try.  I hope this information helps.