Wiring on 287707 1255-E3 Motor

[pickenspolitics]

My wiring situation on my 1996 Craftman with a Briggs and Stratton motor (287707 1255-E3) is a mess.

I think I figured out. See picture.

From the key the M or black wire is going to the black wire on the motor. A1 or blue wire from the key is hooked to the gray wire (carb solenoid). A2 is an orange wire from the key and it hooks to the red wire on the motor (alternator).

Does that look correct to you?

What is this black wire coming from the motor near the top? See picture (red circle with question mark). Someone said it was for the lights.

 

[bertsmobile1]

Take the blower housing off and check
IF the stator has a red & a black wire coming from it then yes the red goes to the battery VIA A DIODE OR RECTIFIER and the black was AC feed for the lights usually hard wired into the key switch .
Check the magneto kill wire that comes off the magneto.
It should go to the M terminal on the key switch.
Very important that this wire is either open circuit = running or closed circuit = off.
I would suggest that you make a jumper connected to it or now that you can touch to ground manually to turn the engine off .
If that wire is connected to the battery or alternator for even the briefiest part of a second you will fry the timing chip which requires a replacement magneto.
So hook the mower up, check the mower side of what you think is the kill wire for voltage with the key in every position then do the same with the engine running before you connect it to the magneto .
The wire is AC so needs to be converted to DC before you hook it up to the battery or you will kill the battery .

 

[pickenspolitics]

Attached is the wiring diagram for the motor.

 

[pickenspolitics]

I took off the blower housing as you suggested. The black wire comes from the stator. See picture. The stator has a black wire coming from it and it is not hooked to anything. The red wire from the stator is hooked with a blue connector to orange wire that feeds back to the key at terminal A2. You can see that red wire, blue connector and the orange wire in the picture below.

I no longer have lights on the mower. Can I just cap that black wire with a wire nut that is coming from the stator?

I double checked and I am confident the magento is hooked to the black wired that goes back to the key's terminal M.

 

[bertsmobile1]

Some one has chopped the plug off the end of the alternator wires
The original plug has a diode connected to it that converts the AC ( like your house power ) into DC like your car & mower .
It is shown as a triangle on your wiring diagram
These go bad over time and B & S do not sell them as a service part thus requiring the home owner to buy a new alternator stator .

Now I made the bold assumption that you did not chop up those wires yourself and that is how you got the mower
If you hook the red wire directly to the mower without either a diode or a rectifier then the battery will not charge and it will be destroyed and may even explode due to gas build up .

 

[pickenspolitics]

I bought it that way. What do you suggest I do?

 

[bertsmobile1]

I took off the blower housing as you suggested. The black wire comes from the stator. See picture. The stator has a black wire coming from it and it is not hooked to anything. The red wire from the stator is hooked with a blue connector to orange wire that feeds back to the key at terminal A2. You can see that red wire, blue connector and the orange wire in the picture below.

I no longer have lights on the mower. Can I just cap that black wire with a wire nut that is coming from the stator?

I double checked and I am confident the magento is hooked to the black wired that goes back to the key's terminal M.

You do yourself a big disservice as you did understand the previous post
Yes you can cap off the black wire with no problems
Briggs did a really good Guide book that is a free download
No you can not connect the red wire directly to the mower it must have a diode in there
Now you have 2 choices
1) buy a diode & solder it into the red wire
2) buy a rectifier
Your original plug looked like this

The diode is the big black blob near the plug but as the other side of the plug is missing the easiest thing to do would be to buy a rectifier like this



The red wire from the alternator goes to the yellow wire
the red wire from the rectifier goes to the mower orange wire
To work the bolt that goes through the hole in the middle must be grounded so either go into metal or have a ground strap
B & S made a new dip stick tube with a spot to mount it but you can put it anywhere you like with some longer wires

 

[pickenspolitics]

Thank you. I will just cap off the black wire and buy that part.

That is easy enough. Where can I buy a rectifier for that motor?

 

[bertsmobile1]

B & S part number 491546
A stock item for every mower shop & every mower parts retailer
Also all the after market parts suppliers
Cheap item even for genuine B & S
If you do the lazy Ammozone-EvilPay route, make sure it is branded as there are a lot of people selling the ones that B & S rejected because they were faulty .
A local mower repair shop ( the type that sells a lot of used mowers ) will have them in stock and probably a used dip stick tube to mount it on.

 

[pickenspolitics]

Thank you for being so nice to me, patient.

Can I mount it to the blower cover?

I will just have to put a connector on the orange wire to make it work.