C2 66 427 AIR Choke Closing When Hot

[Mark]

I have a '66 427 AIR 390 HP car and the choke seems to be running in the opposite way that it should (at least with the 3606 carb). When it gets hot, the coil expands and pushes the choke closed, which causes the car to stall. In actuality, if it were working correctly, it would start out closed and PULL it open. I have looked for other options as far as chokes go, but have only seen one option offered in the various parts catalogs. Is there another choke configuration/option available for my car, or is it hooked up wrong? I've been told there are two different units out here, but can't confirm it.

Any advice?

Thanks,
Mark

[Wayne W.]

Re: C2 66 427 AIR Choke Closing When Hot

The Holly and Rochester chokes work opposite each other. You must have the wrong choke coil.

[Joe L.]

Re: C2 66 427 AIR Choke Closing When Hot

Mark-----

Wayne "hit the nail on the head"; you have the wrong choke thermostat installed. Someone may have assumed that these thermostats "are all the same". Or, they may have known that 68-69 L-36 used a certain choke thermostat and that 66-67 L-36 "must have used the same". Even worse, many GM parts publications LIST AN INCORRECT CHOKE for 1966-67 Corvette applications. Any of these could be the genesis of your problem

You require choke thermostat GM #3887148. It's discontinued, of course, although it was available for a LOT of years. No problem, though. You can obtain a virtually identical piece in the automotive aftermarket. The choke coil you need is Standard Motor Products # CV 24. Many auto parts stores will carry this item or be able to get it for you quickly. They may have the same item under other brands. Make sure that you have them cross reference it frrom either of the numbers I provided. Don't let them go the "application route" or you might very well end up with the same thermostat you have now.

As I say, these units are functionally identical to the originals and their appearance/configuration is virtually identical. The only noticable difference is that the frame of the original thermostats was natural steel. Later GM replacements (of the same original part number) and the Standard Motor Parts thermostats are usually zinc plated. No big deal. The thermostat frame is concealed by the cover, anyway.

[Mark P.]

Re: C2 66 427 AIR Choke Closing When Hot

Thanks, gentlemen. I'll check it out. Sure appreciate the response.

Mark