QuestionHi, Mr. Jones.
Here's what I've got: An MTD Statesman lawn-tractor (Mod. # 13AN678G016 / 103-73424), with a Briggs and Stratton engine (16.5 HP, Single Cyl., I/C)(Mod. # 313777, Type 0163-E1, Code 010405ZE), and a Toro LX500 lawn-tractor, (Mod. # 13AP60RP744 / LX500-621-616), with a Kohler engine (22 HP Courage, V-Twin) (Mod. # SV720S, Spec. # SV720-0011).
The Kohler engine is dead. What I'm trying to do, is install the Briggs and Stratton Engine onto the Toro lawn-tractor. So far, everything works, except for wiring up the alternator. The Kohler engine had two white wires coming from the alternator, going to the regulator/rectifier, and one purple wire from there. The Briggs and Stratton engine has two wires coming from under the flywheel, one black and one red (I've been told that the red wire carries regulated, rectified DC, while the black wire carries AC. In that case, the black wire will not be used for this application, right?).
It seemed a simple enough situation. I hooked the purple wire from the Toro lawn-tractor to the red lead from the Briggs and Stratton alternator, started the engine, and, after a few minutes, began to smell smoke. I cut the engine off, pulled the wires, and noticed smoke rising from the air-intake screen of the engine.
I've run the engine again since (with the alternator dis-connected) and checked for power from the DC lead, which there is, so evidently the alternator's still working (it did not make smoke, either). The purple lead from the Toro lawn-tractor makes a spark, even when the key is turned off (sorry, but I haven't got a working multi-meter). Is this normal?
I strongly suspect a problem in the Briggs and Stratton alternator or regulator/rectifier assembly, but first, have you noticed anything grossly wrong with the way I wired up the alternator? Are additional components required?
Thank you very much for your time and consideration.
---Joe Buaiz
AnswerToro manual link;
https://homeownersolutions.toro.com/portal/server.pt?space=CommunityPage&cached=true&parentname=CommunityPage&parentid=1&in_hi_userid=19462&control=SetCommunity&CommunityID=214&PageID=238#manualsResultPage
Briggs alternator link:
http://faqs.custhelp.com/cgi-bin/faqs.cfg/php/enduser/std_adp.php?p_faqid=26&p_c...
Both sites have great manuals, download for free. The purple wire is the RMC ground wire. When you connected the purple wire to the Briggs alternator harness you shorted the alternator to ground. Most likely you fried the diode due to the direct short. You can replace the diode. The diode is contained in the alternator harness but you will need to identify the alternator, dual or tri circuit, to order the correct part. The Briggs alternator link describes how to identify your alternator.
The Toro charging system wire is the Red/White (R/W) color wire according to the diagram. This wire should connect to the rectified Briggs charging circuit.
Thanks for all the numbers...I was able to look up and provide you links for all the manuals you need to fix your problem. Let me know if this helps.
Eric
I have fried diodes myself. Connecting the purple wire to the alternator caused the same condition as if you connected the battery cables backwards.
I'd recommend reading the manuals, purchasing the correct Briggs alternator harness and a VOM to troubleshoot the mower. The circuits are pretty basic but you will have to do some research to finish the project. Use the Toro manual to identify the charging circuit. The purple wire, when all is done, should connect to the Briggs magneto/coil circuit so the engine will stop when you try to mow in reverse.
