Big Brother is going 3G

[ArdWrknTrk]

I would.
If you decide that you need the extra complexity you need a choke heater to match, or it will come off much too quickly in winter when you need choke most.

Tell us why you can't get your "7V" system adjusted correctly.

[BigBrother-84]

Ok, I had to go buy some wood at the hardware at my chalet.  Took  Big Bro, so did a cold start with air filter lid removed.

The choke flap did as usual:  First full closed, then opened slowly until completely opened.  Nothing special, not faster that usual.
Seems that the current it receives from the 3G is similar than it was from the 1G.

We'll see next winter.

[ArdWrknTrk]

Why would the stator current be any different, one to the next?

[BigBrother-84]

I don't know Jim.  I would answer "why not?"

I don't know if there are significant differences between 1G and 3G other than their performance to produce the same 14V with different amperage.

You can tell me the stator of a 3G is half or twice the alternator voltage, because of some internal construction or electronic gizmos, and I'll believe you.

These things so evident for you aren't for me.
That's why I (and couple of members too, I imagine) need you!

[viven44]

Let me see if I can get this one correct

The choke is the load (or more accurately the coil-deal mechanism that moves it)... so it decides how much power (current * voltage) it needs .... as long as the stator current can supply that much then it is happy... so far I think I am correct ... but not sure about the next part... when you have an aftermarket choke, it wants a lot more power which can be only met with Battery voltage (12.5 - 14V).. apparently the ~6-7V stator output cannot output enough current to make up the difference ... basically current needs to double to make up for the voltage drop.. So am I correct in assuming the status output current is limited internally ??

Regardless, I learned something about 3G conversion that the stator/choke behavior is the same

[ArdWrknTrk]

I get your point V.
You're thinking "pull" (resistive load sinking current) and I'm thinking "push" as in there's no more effort in turning the key on a semi than there is on a moped.

But you want the bimetallic coil on a (nominally) "12V" choke to come off at the same amount of time as a "7V" stator driven choke coil.

It would be interesting to see the numbers on the choke for a 351 HO, and all the rest of the 4180's like my 460 or a 1985 5.0 HO Mustang.
I don't have one that I can ohm out, or look to see if the ID # is the same, but maybe you do?

[viven44]

I have a 351W HO factory carb, about 2 factory carbs from 460s… has assumed all these are stator driven 7V chokes… but maybe the 351W HO is relay driven and uses 12V?? (Which is news to me) I can measure the internal resistance on these….

Actually I need to rephrase. If you have a 12V choke and try to use it with 7V, less current would flow (I=V/R) and thus the slower actuation (isn’t that what happens?)…. So I don’t think there is a “current limit problem” in the stator… choke bimetallic coil’s internal resistance will draw the current based on voltage available … more volts = more current

[Gary Lewis]

Yes, and yes.  The HO choke should be 12V, and they haven't repealed Ohm's law so more voltage means more current and, therefore, more heat.

[viven44]

And then there is the hot air “stove” choke that work in combination with the 7V…. I have seen that combo just once myself… do those actually exist or was I dealing with a swap aberration?? Now that is an attempt to mess with ohms law (sort of kidding ;))… hot air will increase the internal resistance of that coil but also elongates the coil… it will reduce the load on the 7V system in more than 1 way

[Gary Lewis]

It doesn’t work quite like that, as explained here: https://www.garysgaragemahal.com/chokes.html

[viven44]

Well I was really off on that one. Thanks much!!

“as the engine warms up, manifold heat transmitted by hot air to the choke housing relaxes the bimetal permitting the choke to open.”

[Gary Lewis]

I think that write up is wrong.

Since the 351HO has a choke relay and the 460 appears not to have one then they must have had different choke heaters. The only way to prove that is to ohm out the respective heaters.

I have a 4180 off of an HO I think, although I’d have to run the numbers on the carb to make sure. If so I can measure its resistance. But does someone have a 4180 they know is off a 460?

[viven44]

I have both of them. One of a 351 HO truck, and one (maybe 2) of a 460. I had more of these but gave them away to a colleague that liked keeping things original

[ArdWrknTrk]

Is there a unique part # for the 351?

[BigBrother-84]

Gentlemen, following this discussion with great interest.

Although I still have an interrogation, about the "with or without relay" question:
Why the 1984 EVTM has no mention about such relay, for gasoline with idiot light or ammeter.  It doesn't specify any difference between different engines (460, 351 HO, ...).

You have opinion about that, are other EVTM editions different?

If I wasn't on this (wonderful!) forum and just had the 1984 EVTM on hands, I would be sure that Big Bro's choke heater (7V) is perfectly wired, and I would have no idea about any 351 HO choke relay existence.

Or maybe somewhere else in EVTM and I just don't find it?

[ArdWrknTrk]

It's definitely in the '86 EVTM.
I just posted the schematic for someone else.

[viven44]

Good point...

I can see the 1985/86 EVTM showing a choke relay for the 351W 4V HO...
There is no mention of a Choke relay under carburetor circuits on a 1984 EVTM ?

The 351 HO carb I have came from a 1984...

I know Ford likes change.. so wouldn't be surprised they changed things up from 84 to 85....

I would love to be fly on the wall in their change control dept !! Never a dull day I'm sure

[BigBrother-84]

viven44 wrote

I can see the 1985/86 EVTM showing a choke relay for the 351W 4V HO...

Can you post a screenshot so I could see how it looks, and maybe find it in my 1984 edition?

[ArdWrknTrk]

[viven44]

About the 4180 carb differences for the 1984 model year, this is from the factory manual

Looks like 5.8 HO uses 7V stator in 1984