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wiring the new to the old


plastikosmd

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Well after welding up the 16 single, it is now time to drop it in. this 'newer' model has a gear type starter, and a small 2 pin plug coming out of the flywheel housing. I assume the plug is running to some form of mag. question: how to wire this newer system. I assume I still use the old voltage regulator. is one pin stator and other field? (there is also a green wire on other side of block) I could remove starter/cut housing so that starter/gen will bolt up and run it that way but would like to try it the new way. thanks
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The newer under the flywheel alternators need a regulator/rectifier to produce your 12 vdc from the ac voltage produced by the alternator. You can eliminate the entire original volage regulator. Tie the reg/rec output to the B+ where it would normally connect to the regulator.
[img]/club2/attach/ReedS/DSCN1473.JPG[/img]
This was my b112 with a late model 16hp briggs conversion similar to what your doing.
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sorry, I am an electrical idiot. 1) will try to locate rectfier 2) do both pins connect to rectfier somehow? 3) do you have another wire on the other side of the block? 4) looks like you you have that rectifier red to a black/brown then that runs to the postive terminal? thanks reed
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If you have a red and black wire connected to plug, that should be a dual circuit alternator, 12V 3A DC on red and 12V 30 watt AC on the black. The DC is for charging battery and the AC is for the headlights. Briggs has a pigtail harness that connects to the engine harness. The color leads are red to red and black to white. You will need to redo your headlight circuit direct from alternator to light switch to lights. On DC circuit, replace charge wire with new red wire, which should be at ignition switch I think. Also at night your headlights will change in brightness with changes in RPM. Lastly, the magneto wire is a single strand wire sneaking out the side opposite if Magnetron or anchored to a piece of bakelite near points cover.
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I put a circa 1985 Briggs 11HP on my 3410, and ended up wiring it like Reed did. I had to buy a seperate regulator, which plugged into the harness which came from the engine. One wire came off the regulator went to battery +.
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ok, as blt said, i have 1 black/red into a 2 pin plug and 1 green off of the bakelite. 1)recommended source on regulator/type? just ask for a briggs regulator? 2) if both are running into regulator, there must be a second wire running out for the lights? (even if it just passes through?) (did you guys-reed/goat just run lights off battery power?) 3) where will mag wire go? 4) why not run the charge wire right to postive terminal? is it a drain when key off? thanks
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Scott, As bob mentions there are several different versions of the flywheel alt out there, including some that have both a low amp 12 vdc output for battery charging as well as an vac output for lighting. The type of alternator can be identified using the briggs site. How the alternator is wired to the tractor will depend on the type of alternator you have. If you have the dual circiut type you may have either split your wiring on the tractor to accomodate the split system or you may need to change the alternator stator to the larger single 20/30 amp 12vdc type the be able to run all of the elctrical loads on the tractor. I'd personally prefer the straght 12vdc type over the split system. The b112 was a single 12vdc 20/30 amp output. If memory serves the red/brown wire went to the circiut breaker and the red wire from the circiut breaker went the ign switch 12+. I wish I had a better pic of the wiring harness as it's been awhile since I've had this particular tractor here and even longer since I wired it. The purple wire in the photo is the ign kill from the ign sw to the points and the other wires it's tied to went to the lights. Good luck with your conversion.
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mine sorta fits the dual alt wiring as mentioned by blt. Wonder if I need a rectfier with this setup. well, will prob just get it running and see what the output is and go from there. will let you know. and where does that mag wire go then?
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You don't need a rectifier or a regulator of any kind. All you do is slip the boot on the plug coming out from under the flywheel down and you will see that one of the 2 wires has a diode, that's your battery charging circuit. that goes directly to the positive on the battery. You could also splice an ammeter in there to monitor charging. The diode keeps the power in the battery from shooting back to your alternator and cooking it, its like a one way valve it only allows power to go from the alternator to the battery but not vice versa. The other pin on that plug is for your lights, just run a wire off that to a switch on the dash and from there go to the lights. Your lights will however dim as you lower the throttle, at half throttle there is plenty of good usable light. Also the engine has to be running to use the lights. The green wire is probably your kill wire. Hope this helps. Have you bench tested that engine or are you just gonna drop it in and hope for the best?
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I don't have lights on the 3410, so I didn't need the extra wire. I ran lights on my 2110, and just wired them off the battery. If you do what Zach suggest's, I would, at the minimum, put a meter on that output wire, to see what it's putting out voltage wise.
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well starting didnt change much, now i gotta do the charge/lights. if anyone has an old harness laying around let me know. I could use the clip at the end that will hook to the red/black. that will keep me from having to cut/splice
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my nearest junkard is on my property! but seriously, none round here that i know of. I can just make something, no big deal
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