Hello All,

1983 Ford Bronco, 300 (big six), NP435 with a swapped 2100 carb (no-feedback, never had it)

The factory (~32 year old) electric choke heating element finally burned out on me. I've ordered a new factory choke for the truck already but while I wait I have a Holley electric choke that I swapped in. I should have just left the factory one in even with the burned up heating element but......

I have the Holley electric choke positive hooked to the factory connector which I believe comes from the stater on the alternator. This provides roughly 7 VDC (I rbelieve it is actually an AC voltage). The Holley I believe is supposed to get a 12v source but seems to heat up just fine on 7 VDC. The ground wire for the choke I simply connected to the carburetor, which is grounded.

So here's my issue only since I have swapped in the Holley electric choke....

When I first start the truck when its dead cold I hear an audible electronic buzzing (high frequency). After about 5 seconds it goes away and as long as the truck remains even just a little bit warm it does not return. It only occurs with the truck running and not simply with the key in the ignition.

Is the temporary Holley choke pulling to much current and setting off some sort of alarm from the alternator? I wouldn't think it would even have this feature. I'm just trying to make sense of it. The truck seems to operate just fine but don't want to damage something while I wait for a new choke. In the mean time will probably just disconnect the heating element.

Thanks,
Dan

 

You need the choke.

It could be a noise coming from the alternator because of the load on the stator circuit but there is no 'alarm' that I know of.

 

Pull the wire off to make sure it's the problem. If it still does it, but not with the complete holley choke installed, I be you have a vacuum leak in the choke area. Ford put vacuum on the choke housing so it pulls warm air from a tube that goes through the exhaust manifold. If your Holley choke is not fitting right on the Ford carb, it could be leaking vacuum and making the noise.

 

Ah, yeah, one of those doodads in the air cleaner, those things can "buzz" as such.

But so can a voltage regulator.