66 issue - help

[Rob M.]

Hi all,

I hope some of you more experienced members can give me some suggestions. Here's the senario:

I just installed a beautiful, Jerry MacNeish rebuilt 3367 Holley on my 327/300. I replaced the PCV and all appropriate gaskets/heat shield. After adjusting the carb, I can't get the car to run right. It idles at about 700/800RPM and the and the idle adjust is set as far as it will go. The butterfly valves are all the way closed. If I pull the PCV line and plug it, it only drops the idle speed by @200 RPM's. My assumption is that it's getting air from somewhere, perhaps the intake manifold gasket is bad?

Any suggestions would be appreciated.

Thanks in advance,
Rob

[Wayne W.]

Re: 66 issue - help

Make sure that you have the SS plate next to the carb and the gasket on the manifold.

[Rob M.]

Re: 66 issue - help

Wayne,

Did that. No better. Even tried an extra gasket between SS plate and carb (in addition to the normal gasket)that may have helped just a little. It must be getting air from somewhere. Very frustrating. I must have pulled that carb 6 times already trying to get things right. I may have to take it in and let the local corvette restorer/machanic look at it.

Thanks for the response.

[Verle R.]

Re: 66 issue - help

Wayne,

With the engine running spray WD-40 around the base of the carb a little at a time. If the engine speeds up you have found a vacuum leak. If the carb base gives no results spray around throttle shaft in the base plate, any vacuum port, vacuum hoses, the edge of the intake by the valve covers.

Verle

[Shannon Burgess]

Re: 66 issue - help

Rob, the steel plate should be against the carb with no additional gasket between the plate and the carb. The carb gasket goes between the manifold and the steel plate. Without the steel plate immediately below and against the carb there will be an internal vacuum leak between the warmup crossover passage and the carb. It will not be detectable from the perimeter of the carb to manifold mating surface. I learned this lesson the hard way on my '69.

Shannon

[Rob M.]

Re: 66 issue - help

Thanks for the advice. I'll give the suggestions a try.