1969 Carburetor Replacement with Electric Choke Question

[RichV13]

Hi, I recently had my new acquisition checked out by a local mechanic, the only negative he came back with was fuel leaking at the carb. It's been 35+ years since I tinkered with a carburetor. Money and skills analysis determined I was willing to replace it rather than rebuild it. I've got an Edelbrock 600CFM with Electric Choke waiting to go in (still waiting on every possible Edelbrock accessory kit to arrive before I make the swap. I've read the manual, watched all of the included videos and I'm prepared for the task, but I have a few questions.

1.) Electric Choke connection. I found a mix of years where this topic came up, some recommending the "S" wire off of the alternator, others suggesting going to the fuse panel. What current will this draw? Is the "S" wire the same as the "Stator" Terminal? Is this ok to use?

2.) Distributor vacuum port - timed or manifold port? I assume manifold as I don't believe there is emissions equipment on this car.

3.) As I said I bought all of the possible accessory sets and will return the ones I don't need. There is mention of a heat insulator gasket if the hot engine is difficult to restart after sitting for 10-30 minutes. It sounds like this may only be necessary if mounting to an Edelbrock performance intake manifold, I still have the stock manifold. What's the likelihood of needing this?

I think that's all for now.

Thanks in advance for the help.

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[Toothaker]

Congratulations on your new acquisition!

1. Electric choke. That wire heats the spring, which is itself temperature sensitive, and 'turns off' the choke a little earlier/faster. This is needed in the winter to stop the engine from running too fast after warming. You will need to fine-tune the amount of choke, and you will find that there's a summer and a winter setting. Helpful, huh? 🙂 You may even find the wire is unnecessary, as the wire only speeds up the adjustment of the choke. It works without the wire, just changes more slowly as the engine bay warms.

Edit to answer the rest of the question. You need to find 12v switched from somewhere. Switched, so that it is off and allowed to cool when the car is off, and so there's not a drain on the battery.

2. Manifold is what you want. The 'timed' port was used for a badly designed first-generation emissions system that retarded ignition timing at certain speeds. In fact, it did not reduce emissions and it made the car lug when it was active. Not sure if this was something on the 1969, but it was present on the 1970. If you have a air fitting on the thermostat housing, which is also part of this system, then you have it too. It was trivial to disable. Cap the fitting on the carb.

3. Carb heating causing restart issues. This can happen if you have an aluminum or an iron intake manifold. The heat insulator will raise the carburetor and air filter housing, so check your clearance to your hood. This (the hot engine restart problem) is an issue in the warmer parts of the country in the summer.

 

[RichV13]

Follow up: When eliminating the Choke Stove, is there a known aftermarket cover to take its place? I don't currently have access to resources who could fab something for me with relative ease 🙁. I could cut the rigid line that was the clean air side of the tube and cap both clean/dirty lines. I have to remove the choke stove or trim the line as the new carburetor won't sit down properly otherwise.

As always Thanks In Advance for any ideas.

Rich

 

[Frankie the Fink]

I have found that the electric chokes tend to "pull off" too quickly and that may, or may not, cause problems... They can also burn up if the key is left on and the choke is wired to a switched source and the engine is not running because of lack of air flow.
Hard restarting or "heat soak" can occur with cast iron manifolds, its very common - I wouldn't do anything special unless you actually encounter it, it seems some cars never experience it while others are plagued by it.
Full manifold vacuum is preferable for vacuum advance purposes, the car will run cooler and smoother; especially at idle/
Frankly IMO you'd be better off rebuilding the original carb or finding one, as now you'll be fiddling with throttle linkage, possible hood clearance issues and fuel line rerouting and the result will be a sub-optmal "one size fits all" carb setup and not a factory tuned and design setup.