Choke Tube Options

[Kenny G.]

I bought my first Corvette a few months ago after years of dreaming with my wife (both of us drove restored 1957 Chevy Bel-Airs to high school when we met in the late 80's).

Our 1960 Corvette has an exhaust manifold on the passenger side with an unused hole for the choke tube and hot exhaust has been blowing onto the fresh air duct under the hood and eating it away. Because the previous owner installed a new carburetor with an electric choke, I would like to plug the hole so I can drive the car, but would like to be able to go back to the choke tube if I ever get the correct carburetor. I thought of putting in a choke tube and pinching the end off under the air cleaner so that it looks correct at first glance temporarily. Any other ideas on a quick fix for this problem?

[Dan H.]

Re: Choke Tube Options

Hi Kenny, congrats on the new toy! It sounds like the exhaust manifold internal heat tube has sprung a leak! Your best bet would be to replace it with a new tube and that will solve your problem plus leave the car 'stock' so if you return it to original it can be done!
Dan

[Dan H.]

Re: Choke Tube Options

Kenny, the really bad thing about that tube blowing out is you guys are getting exhaust back into the cabin, makes for a bad headache! The best fix is to remove the manifold and do it correctly (tube removal/press in) then you're all set cruisin!
Dan

[Kenny G.]

Re: Choke Tube Options

Thanks for the info. Exhaust in the cabin is my excuse to only drive with the tops off.

Are you talking about removing the tube inside the manifold and pressing in a new one?

[Dan H.]

Re: Choke Tube Options

Thanks for the info. Exhaust in the cabin is my excuse to only drive with the tops off.

Are you talking about removing the tube inside the manifold and pressing in a new one?

Yes, then check both sides while you're at it for leaks, then enjoy!!!

[Jack H.]

Re: Choke Tube Options

Dan's on the money here... The fresh air tube through the exhaust manifold stands in middle of the exhaust stream inside the manifold. Over the years heat + moisture result in cracks in the tube that admit hot exhaust gases.

When these are connected to the choke on the carb, you're literally playing with fire! You're testing the integrity of carb's choke in terms of sealing. If the seal isn't perfect, you risk running red hot exhaust gas into the carb with a KABOOM threat looming!!!!

The tube is press-fit into the manifold and replacement tubes are listed in most all of the catalogs. This is one of the first things to consider on an aged classic Corvette and replacing the original heat tube is a REAL good idea.

If done properly, the lower end of the tube should seal against the manifold wall and allow only fresh air to enter the tube. The same goes for the upper side of the tube.

If the tube isn't connected to the choke on the carb, all that should emerge is air that's been warmed by the manifold and the convection flow from the lower to upper end of the tube.

[Kenny G.]

Re: Choke Tube Options

I got the picture now. Now I just need to order the inside tube and get it inserted in the manifold. Thank you very much for your help.