Well I think the carb shop in California that checked out my dual quads may have just fixed me up. I'm running on just the rear carb right now while the front one is back to them for a repair. The car initially ran rich in the garage with the choke full on and me adjusting the idle/mixture. Plugs were fairly sooty again.

Road tested it for about 20 minutes keeping the RPMs fairly high. Car runs and idles nicely. Came back and pulled the plugs and the electrodes are clear now which never happened before with these carbs. I hear this is fairly normal for the old dual quads. (Loads up at idle and 'blows it off' while driving.) This is the same results I had running a DIFFERENT WCFB I scrounged off a board member here that I rebuilt myself. Is this what I should expect ?

Seems the floats were off but mainly there was some kind of Topco (a company) diaphragm replacement in place of the needle valves in the carbs that never really 'closed off' - dumping fuel into the bowls full time. Correct needle valve replacement and float adjustment seems to have been the answer.

I'll feel better when I'm running both carbs and have the same results but I wanted to thank Plasticman, WMF62, DevilDog, Old Heap, Ironcross and I don't even know who else for 'crisis intervention' during this mess ! I'll report back when I have both carbs on and tweaked up.

 

Easy check to see if floats are to high remove Carb side screws, if gas pours out they are to high

 

Really - first time I've heard that one, even on this knowledgeable forum.

Truth be told now that I've rebuilt a spare WCFB I'm confident enough to tear these bad boys down and rebuild them if needed. They really aren't that bad.

 

Now, that is the spirit !!! They are fairly simple, just look complex. Now, just put them in a shotgun set-up and you can suck asphalt on your street and terrorize the neighbors.

Joe

 

And suck greenbacks out of my wallet !

I'm happy with them in the progressive setup I think. I'm told these cars are a little 'squirrelly' with the shotgun deal - but I may try it some day.

 

For street driving, the progressive is the best way to connect the linkage. If the ocassion arises that you really need more throttle response, or even full response, simply depress the gas pedal more. The way the 2x4 linkage functions, even for race conditions, I'm not totally sure that the shotgun setup really improves response over the progressive setup.

 

I never found it to make any improvement. Different feel. Maybe road racing, the throttle response would be improved.

 

fdreano, What is the casting number on your center section (float bowls) of your carburetor? I've got the correct 2626S and 2627S carbs on my 59, but neither have the screws that 1955 Copper refers to. Was this an earlier or later addition to the carbs? It would be great to have those screws to check float level. Kinda like a Holley! I wonder if they could be added? Hmmmmm........

 

Tom, I agree. I run mine street and track with progressive. I was just tweaking Frank a little. As with all carb set-ups, more imprtant to be sure linkage is not blocked by carpet, ignition shield brackets so they do open fully.

Joe

 

It was an early 55 to 58 that I know about later years I dont know, but the gas should JUST be at the bottom of the holes. An easy check and it works!

 

The tops on my current carbs are 1151 and 1156 both bodies are 049 and the base has the correct idle bypass screw for '56 so I think they are correct for that year but not '61 270HP.

I like the screws if they truly work for float level - I don't know what else they would be for but haven't heard elsewhere that this is their purpose - that would indeed be like my old Holly dbl pumper (I miss it dearly).

 

i would be interested in where it is you have seen this procedure spelled out. i have not seen it anywhere in my travels.
is it in the ST-12? in rebuild kit literature?
i've used it on Holleys. but never on WCFB's. Seems odd because the recommended float levels, primary and secondary, are different specs. these plugs are at the same height.
BTW, some WCFB's do not have these plugs. They are on most i have seen, but not all.

 

I know 55 to 57 for sure have them for later ? But anyway when you remove the screws the gas should just be at the bottom of the screws hole ( no gas flowing out) , done this on many Carbs for owners , if the floats were set correct .if gas is still coming out then the needle and seat are leaking like you said it was. It's just a simple way to check the float level while running at idle.
Same thing checking the fuel meetering rods( take the front top cover off loosen the screw lock to let the meetering rods to be pulled all the way down while idling then tighten the screw).
By the way add the by-pass bushing tube to keep the Carbs from flooding on left turns.
I was a mechanic on Corvettes in the old days and that is how we did it!

 

The idle mixture should be set with the engine at operating temperature and the choke completely OFF.

 

I would love to know from someone if the screws are countersunk or not. It looks like Roy's carb picture shows countersunk screws that are most likely fine thread for liquid sealing. If these were added to an original carb do you feel that it would hurt their value? Also, does anybody have dimensions for locating these screws in the side of the casting? Thanks.

 

that's what i thought. nothing in writing though.

 

Coves4me, from what Bob Kuntz told me is the ones you have are like mine, an over the counter replacement. They are correct in every way but do not have the float check screws. The screws are not countersunk but have a lip on them. Bob Kuntz tapped mine and now are correct. best scott

 

Look at it this way - what other possible use could these screws be ? Seems like that was the intention by the designer(s).

BTW - Ran my vette for a good 45 minutes at all speeds today and it was a genuine pleasure to drive - NO MORE RICHNESS. Checked plugs after this run and they look really clear and burning properly. Been fighting this problem for 4 months and finally done with it. Amen!

 

Congrats!

Plasticman

 

i can't remember if you said your carbs had these screws or not. but if they do, and you have one that is fresh from the rebuilder, did you try removing them to see what happens? just curious.