Holley 4150 Carburetor - Is this the vacuum and what is the 2nd electrical plug for?

[Midcont]

Sorry, I'm not the most knowledgeable on carbs, but what is this second power connection for? Why is or in this case, why isn't it used?
Would appreciate if somebody could give me a breakdown of how this works or maybe a link to a youtube video that shows it specifically.

[Grubby]

The electrical connections are for your electric choke. One is B+(12v) and the other is ground.

The ground has been grounded to the carb. It should work like that.

Then just run a wire from a source that has B+(12v) when the engine is running. It is really simple.

John

[Midcont]

Originally Posted by Grubby

The electrical connections are for your electric choke. One is B+(12v) and the other is ground.

The ground has been grounded to the carb. It should work like that.

Then just run a wire from a source that has B+(12v) when the engine is running. It is really simple.

John

You are saying a 12v line should be run?

[TButtrick]

Yes, 12VDC to the bare terminal in your photo. Take a look at 1:45 in this video;

https://youtu.be/a81YNfOFVKg

[Midcont]

Originally Posted by TButtrick

Yes, 12VDC to the bare terminal in your photo. Take a look at 1:45 in this video;

https://youtu.be/a81YNfOFVKg

Ok, thanks for the link, very helpful.
Just so I'm understanding here:
The choke has never had power running to it. Why would't it have been powered?
Is there any risk or negative to adding power to it?
How would adding it change my startup procedure?
Any effect on the engine once running or warm?

[cycleguy55]

Originally Posted by Midcont

Ok, thanks for the link, very helpful.
Just so I'm understanding here:
The choke has never had power running to it. Why would't it have been powered?
Is there any risk or negative to adding power to it?
How would adding it change my startup procedure?
Any effect on the engine once running or warm?

Q: The choke has never had power running to it. Why would't it have been powered?
A: Somebody forgot to hook it up.

Q: Is there any risk or negative to adding power to it?
A: Not in my opinion. One thing I will note is the choke pull-off has to be properly set. On my car it wasn't pulling off far enough and the engine (460 CID) wasn't getting enough air on fast idle and was choking itself. A minor adjustment fixed that quickly enough.

Q: How would adding it change my startup procedure?
A: Do this:

1. Turn the key to ON position
2. Floor the gas pedal and release (anything beyond about 1/8th is probably sufficient, more if it's quite cold)
3. Start the car

Starting Question - electric choke

Q: Any effect on the engine once running or warm?
A: It will fast idle until the bi-metal element in the choke warms up sufficiently. At that point you'll be able to 'blip' the throttle a bit to 'kick out' the fast idle cam and let it return to normal idle speed.