Husqvarna start switch wiring, Briggs 12hp

[trouts2]

Husqvarna riding mower RT11 with a Briggs I/C 12 hp. It is not an RT111. It is older.
Bear with me on this. I do a lot of work on older snowblowers and chainsaws but not much on Briggs or riding mowers.
The rider got rained on and the start switch filled with a couple ounces of water. The batter fuse blew and would not start after that. I got the machine used. It had harness mods. The safety switches were by passed and I’m not sure what else. The wiring harness below the operator seat by the frame got chewed up about 4 years ago. I cut from the back wheels forward, soldered in new wires and put a harness sheathing around it all. I think I wired it right but not positive. It started and stopped fine. The lights wires were cut out by the prior owner. The charging circuit did work as it would start all summer so I assume that wiring was ok.
When I put in the last switch that got messed up with the water it did not match the manual. The mower is a Husqvarna RT11. I don’t have the manuals for it so using the RT111 schematics. The switch letter pinouts are different than the 5 position switch I replace with. The current switch I have has the same letter pinout. My current switch pinout is this:
M
B S
G L
B , From battery, to fuse to B on switch.
S, Runs straight to the solenoid plunger +.
M, I think runs to the coil grounding wire. The engine does stop in the off position.
G, Runs to ground. It is ground but I’m not sure if the proper ground wire.
L, A blue wire and for now unconnected.
This switch does not work exactly as the RT111 switch. It works as follows:
OFF, M to G
On, B To L
Start, B to S ( the manual has B to S and L)
My problem with getting the new switch working was fuses would blow after I plugged it in. It started once but after that blow a fuse on each start. I took it apart to see if I could find anything but did not. It would not make a connection from B to S so I got another switch.
The new switch is wired as above.
The problems are this and any help would be appreciated.
That is I have a ground but not sure if it is the right ground wire.
There is another wire that comes out of the harness by the switch. It is red and was connected to (soldered to) the B (battery) wire. I have left that unconnected. I think it may be to the charging circuit. It has 12 volts on it when the engine is running. It ohms out to a red wire up by the engine. That wire, up front, comes out of the harness with an orange wire to a connector. That connector plus into another connector with two wires that run under the cowling behind the starter. I think it is probably the output of the charger but not sure. If you know what those two wires are please let me know. If that is the charging wire should it be connected to B on the start switch?
There is another single black wire coming out of the front of the cowling. From the drivers set it is on the left side of the engine. It runs to a fixture holding the throttle wire. It mounts to that fixture with a red wire that continues on to the harness. Is that the engine kill wire?
I have two mulitmeters but got fuzzy readings when buzzing out the wiring. They are not reliable and part of the problem.

 

[trouts2]

There are a few versions of LR111 manuals which have different pinout arrangments for the start switch. I'm pretty sure the black wire comming from under the engine cowling on the left side is the coil grounding wire so that went to M.
One of the two wires coming out from the right side of the cowling by the starter was red and the charging wire. Some drawings have that going to B, doubled with the fused line from the battery terminal. The drawings that show the double on B leave L unwired for some reason. Since L was open and connects to B in the run position I connected that directly to L. Doing that gets the L charging wire to B in run and the battery charged to an cleaner hookup.
Some of the schematics I think are for later versions of the LR111. One odd part is some have the start position connection listing as START connects B S and L. Since L on those drawings have no wire running to L it is strange that would list L as in use for starting. ??
The switch is connected and the machine running fine.

 

[Lubener]

Sounds as if you disconnected things w/o a plan. If you have an exact replacement part and either make a sketch or move wires one at a time onto the new switch things should work. You must have the wrong switch for your model and or the wiring is incorrect.One must know their limitations and I think you reached it with this project.

 

[mk378]

Mowers that don't have an electric blade clutch generally don't have anything 12v energized in the run position, except some have a fuel cut solenoid on the carb. If there is nothing electric on the carb, mechanical blade clutch, and a small two wire plug on the alternator, this is what you have.

The lights (if any) are powered directly from a lighting coil in the alternator. This is a separate circuit from the engine to the light switch (if any) to the bulbs. It is AC not DC.

The ignition switch then only needs to do M to G to kill the engine in off, and B to S to engage the starter in start. The charging wire from the alternator (the one that has a bulge in the wiring on the engine side, this is the rectifier diode) is generally unswitched.