Small Engines (Lawn Mowers, etc.): Charging circuit, full wave bridge rectifier, briggs and stratton

Question
I replaced the engine on a Troy built tractor (1 cyl 15 hp B&S) with a B&S 18 hp twin cyl. model 422707. The 18 hp has 3 wires coming out from under the fly wheel, 1 is black (which I have confirmed is the kill switch. Then there is a red & a white wire. The red wire shows 8.5 volts dc to ground or 18 volts ac to ground. the white wire shows 1.5 volts dc to ground & 0 vac to ground. from red to white it shows 11 to 15 vdc depending on engine speed. If either wire is grounded it sparks severely. Do these need to go to a full wave bridge rectifier (4 diodes) or am I missing something?


Answer
 Hello Dave:

 Do you have the Voltage Regulator Installed? Go to this Addy  http://www.outdoordistributors.com/ and Click on the B. Then Select Briggs and Stratton. Then Select Dont have Part Numbers. The Select Folder # 42. Then Scroll Down to 422700 File and Download. The Regulator is Shown on Page 8 of 9. Diagram # 501. You want the 10 to 16 Amp Regulator. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

 Good Luck

 Respectfully

 John