IH 300u ignition switch wiring question

[ih300u]

Hello all,

I am currently in the middle of converting my 1955 international 300 utility from a 6v system to 12v. Alternator is delco 10SI 3- wire. I have found a lot of wiring diagrams posted here and other places, but they only seem to show the schematics using the original 2 pole ignition switch. At some point in this tractor's history, the original ignition switch was replaced with a D-R keyed 4 pole switch, with posts for IGN, SOL, BAT, and ACC. I have a few questions about how this changes the wiring setup.
1) Most diagrams I have found show BAT on the alternator hooked to the ammeter, terminal 1 on alternator hooked to the run position on the 2 pole ignition switch with the wire going from there to the positive post on the ignition coil. Where will alternator terminal 1 hook up to the 4 pole ignition switch? I assume the IGN post connects to the positive post on the coil.
2) Same diagrams show wire from the other side of the ammeter running a wire to the solenoid. I assume with a 4 pole ignition, the SOL post is for a wire running to the solenoid. Does the ammeter wire still run to the solenoid, or is just supposed to get hooked directly back to the + battery terminal?
3) Same diagrams show the headlight switch hooked to the ammeter on the same side that the alternator wire hooks to. Should the ACC post on the ignition be used for this instead?
4) Where does the cigarette lighter wire fit into all of this? Is it ok to hook it to the ammeter for an always- hot lead? or should it just go straight to the battery?
5) Do I still need to install a diode in the wire going from the ignition switch to the coil? Or is a keyed ignition switch sufficient to prevent backflow from the alternator when turning off the tractor?

Thanks alot for any info you guys can provide.

 

[Soundguy]

Here's what I'd do..

line from alternator charge stud to one side of ammeter. other side of ammeter to battery.. usually by the way of the hot side of the start solenoid or manual start switch on some models.

now, tap all electrical loads from the same side of the ammeter as the alternator.. IE.. wires for lamps fromes from alt side of ammeter to fuse or fused switch, then to lamps.

line runs from alt side of ammeter to intup ost on your key switch, .. run side of key switch thru any resistors and the coil.. start side of switch, if used, can control a starter solenoid. accy side of switch, thru a 194 lamp to the alternator '1' terminal.. this is the excite line. with key on, lamp should glow.. when engine starts and rpm hits about 400, lamp should go off, indicating charging.. this is the 'idiot lamp' method. Yes.. you could also use a diode capable of 3 or 5a and 50 or 200 PIV in place of the lamp, and wire so that the cathode side of the diode ( has a stripe ) is toward the alternator, and anode toward the key switch. this does not have to be on the accy line, could be on the same line as the coil.. as the lamp or diode provides isolation and prevents alternator backfeed to the ignition when you kill the switch.

# 2 ont he alternator can be loope dover to the charge stud.. this is external voltage sense... in a car with 30' of elec harnes, you would actually run this to bat hot post so alt could up the charge for votlage drop int he long harnes.. since your harnes might be all of 3' long.. looping to charge stud is fine.

now you have a net charge / discharge setup with idiot lamp or automagic diode.. if meter reads backwards.. swap wires side to side.. just remember one side has only one wire.. the bat.. the other side is all the rest of the loads AND the alternator charge wire.

soundguy

 

[ih300u]

thanks for the help soundguy!

so to clarify which post goes to which wire-

BAT to alt side of ammeter
SOL to solenoid
ACC to alternator post 1(thru lamp)
IGN to +coil?

 

[Soundguy]

Assuming that key switch has bat common to ign, acc, and sol when the key is turned to the spring loaded stop, and then when you release it to it's resting running position, bat is common to ign and accy, and then when you turn it to acc, then bat is ONLY common to accy, and when off, bat is not common to any other post.. then yeah...

soundguy