I tried to do a search on this, but couldn't find what I was looking for so here goes. My Dad has a 50 F-1 with the original Flathead and a Ford alternator and regulator. The truck has not been driveable for a while as he is finishing restoring it, but he appears to have messed up the wiring and the truck is not charging. My Fords are original generator setups and my other vehicles are GM single wire, so I need a quick class here.

1st- The VR has I-A-S-F I am assuming Instrument,Armature,Stator and Field,is this correct?

2nd what does each of these do and what should go where. The alternator has Grnd,Field and Battery on it. What would be the proper wiring path for this? Right now he has Alt/Bat going to A on VR. S going to circuit breaker then to solenoid and Alt/Field going to VR/Field. I don't think the juice can pass this way and the vehicle is discharging. Can any electrical gurus get us straightened out here?

Thanks,

 

I = ignition, A = armature, S = stator, and F = Field.

I is routed to the back of the ignition switch through possibly a green and red strip wire. But it does end up on the C part of the switch.

A routes from the altenator to the VR and has a wire spliced from the VR A input to the solinoid through a circuit breaker. If you have an amp meter the wire routes through the loop on the back of the gauge then to the solinoid.

G is the ground on the altentor which should attach to one of the VR mounting bolts.

S and F both go directly to the VR from the altenator and nothing else.

One note to help the system a little more. Sometimes the firewall connectors have a bit of corrosion that build up and prevent the system from being flashed by the ignition switch or the routing voltage up to the solinoid via the amp meter loop wire. So disconnect the connectors and clean them out and use some dielectric grease.

 

When you get the wiring sorted out you will probably have to re polarize the generator. Here are a few tips on the subject that I learned from one of the knowledgable members here (Thanks mtflat);

With the engine off, at the regulator, remove the field (F) wire and briefly touch it to the batt (B) connection. You should see a small bluish spark. Re-connect the field wire and you're done. This is per the shop manual.

Do not use a jumper wire - you can cause damage.

Good luck
Bobby

 

OK still a little confused. Where does the battery terminal on the back of the alternator route to? I assume F on the alternator goes to F on the VR. There is no S on the alternator so what goes to S on the VR?

Thanks,

 

If it's an alternator and not a generator here, the alternator for the battery should have a plastic red ring on it. It's usually the biggest terminal also. Merely run a wire 8 ga wire, from that to the starter relay (battery side).

 

A pic is worth a thousand words :-) I think pretty much all alt/regulators were wired the same...... so this link may clear it up.

https://www.ford-trucks.com/user_gal...=16603&width=0

 

Here's another diagram that may help...

 

Ah crap GreatNorthWoods ...........yours is a prettier diagram :-)

 

Well...your's was good too. Perhaps between the two of them we helped some.

 

Sparky!!On your drawing you have a wire going fram the S on the altenator to the choke!!Could you explain more about that wire please.On my 351 W I have a wire from my choke that goes nowhere,so I connected it to the ballast resistor on the ign side. It is at least not long enough to get to the altenator and it looks like it originally went across the top of the engine towards the firewall. can anyone tell me what this wire is for please. Erik

 

I assume you have an electric choke on your carburetor. It can be connected to any source that's hot when the switch is in the "on" position. The ignition side of the ballast resistor would work.

 

The later trucks, 60-70's, used the "S" on the alternator as a convienient spot to power the electric choke coil.......purely optional and nothing will go bad if it isn't hooked up........

 

Maybe this will help or maybe totally confuse. Anyway, here are two more diagrams. I found them in a Motors Truck Manual. They are for Ford alternators and regulators used from the early 60's through the 70's.

The first diagram is for a dash with an idiot light. The 'S' terminal of the alternator is used to trip the field relay in the regulator and turn off the light when the alternator starts charging. I can see how this could also work an electric choke.

The second diagram shows the arrangement using an ammeter. Here the alternator 'S' terminal is not used. So if the alternator doesn't have an 'S' terminal, no problem. Wired as shown, the field relay of the regulator is simply used to reduce the current load on the ignition switch. It would work to wire the ignition switch to the 'I' terminal and eliminate the 'A' and 'S' connections at the regulator but then the ignition switch would need to carry the field current.

All wiring for alternator can be 16 ga except alternator output through the ammeter to the battery should be minimum 10 ga. I would advise putting a 50 amp fuse between the starter relay post and any connections. If the stock '50 dash ammeter is used I like to put a layer or two of heat shrink on the wire where it passes through the ammeter loop. I think it's a likely place to develop a short. For neg. ground the 10 ga wire from the battery passes through the ammeter from drivers side to passenger side and terminates on the common buss for the circuit breakers. From the same terminal on the circuit breakers continue the 10 ga. to the alternator post. Power to the ignition switch also comes from the circuit breaker common buss (16 ga.).

 

Thanks for all the responses. Will let you all know what we come up with.

Thanks again

 

In reference to the orange wire and the white and black wires being hooked up to the alternator. If these were hooked up backwards...(yes i'm an idiot) could it damage the components at all???? I've got a f100 302 that i am having electrical difficulty with.. namely a battery drain coming from the alternator or components... i know nothing about electrical stuff on vehs.
thanks,
cj