Holley flooding

Any suggestions? I have a Holley 600, been sitting for about 5 yrs while I refurbished the body.
After completing the body work, took the truck to chassic dyno for tuning. He has the fuel air dialed in, but starts hard, press the pedal to the floor to start, and a lot of white smoke.
Is this a matter of adjusting choke, or,floats off, or something bigger going on?

[bamabaxter]

I had a problem with mine after I bought it. It was a used 670 and the secondaries flooded out over the top of the carb when the motor was at idle. The needle valves have rubber seats and had dry rotted. 6 bucks later and a little adjusting of the floats and it worked fine. If you don't already have them, spend ten more dollars and buy the clear sight plugs. Trust me they are worth every penny. Hope this helps.

If I change my float level will that also affect the mixture?

[72-c20]

if it was sitting for 5 years, it may have varnish in it that is gumming stuff up. I had a holley I just replaced that had sat for a while. the back throttle plates were closed and sealed, creating a pool of gas that would then cause it to flood out.

I just replaced the carb with another one, but the old one would need a rebuild....

[VetteVet]

If I saw white smoke I would suspect anti-freeze or trans fluid. Black smoke indicates rich or flooding fuel. blue is usually oil and if it clears up it usually means oil has drained past the valve guide seals while sitting. FWIW

[smoknbarrels]

Originally Posted by VetteVet

If I saw white smoke I would suspect anti-freeze or trans fluid. Black smoke indicates rich or flooding fuel.

I say the same thing. especially if there is a ton of it! sounds like a head gasket is toast. I had a holley 600 on a 350 of mine and it takes a lot of rich adjustment to make it not start or create some black smoke.

[bamabaxter]

Correct me if I am wrong anyone, but I think that float level doesn't change your fuel mixture (or the effects are too minimal to account for anything). Your jet size decides what A/F is. I would just try to rebuild it personally. Usually that is what one really needs that has been sitting around for a while. The old gas inside gums everything up. Have you tried just spraying a good can of carb cleaner in it? As far as the smoke goes i definitely agree with everyone else.

[Wrenchbender Ret]

[QUOTE=bamabaxter;2763923]Correct me if I am wrong anyone,

You are. The float level changes the mixture drastically. It should not be used to alter the mixture though. The carb is desighned for a specific fuel level. Any alteration from it will have bad effects on it. You are correct that the metering jets, idle mixture adjustments, & power valve can be changed to modify the air fuel ratio. Before making any adjustments make shure the fuel level is corrct.

[bamabaxter]

Sorry,I didn't think that it had that large of an effect. Sorry if I was misleading. Learn something new everyday. I just thought that you had to correct for the jet sizes. Now that I think about it I guess that doesn't make any sense since the float controls the level in the first place. Does it have to do with static pressure in the bowl and the pressure drop created by the venturis? Does the higher level cause more fuel to enter the main body? I am sorry for jacking this thread.

[VetteVet]

This may help or maybe not.
http://www.lbfun.com/Corvette/Tech/v...a%20holley.pdf

[LONGHAIR]

That's a pretty good all inclusive article. The only thing I have an issue with is the whole "ported spark" thing. I really don't know why Holley keeps pushing that?
I would bet that a lot of guys have removed their new carburetor, calling it "junk" because of that.

[mr48chev]

You said you "refurbished" the body. We are assuming that by this you cleaned up the outside of the carb. Did you put a kit in it then?

If not, I would go ahead and put a kit in it and freshen it up.
As 72_C10 said, 5 years is a long time for a carb to sit. I would get the proper Holley brand kit with the blue gaskets so you can pull the bowls back off to change jets or make other adjustments if needed. Other kits work and may be less expensive but in the long run I have always had better luck with the factory kit when rebuilding my Holleys than with the kits you get at the parts house.
The good thing is that they are fairly easy to rebuild if you take your time and read and follow the directions. Make every adjustment as specified and you should be in good shape.

And yes float level is probably the most critical adjustment on the carb.

The July 08 Car Craft has a pretty good article on Holleys and carbs in general. It does a decent job of explaining how the carb works and what each circuit does. As usual with them it is geared more towards performance but it still is worth reading and saving. It doesn't have anything on working on them, just a good explanation of how things work.

[LONGHAIR]

I assumed that "referbished the body" meant the body of the truck....not the carburetor?

[bamabaxter]

Good article. Again sorry i didn't know it was that important. I just set mine according to the directions and it has worked fine. Still can someone explain the reasoning behind the fuel bowl level's effects? I am not trying to prove anyone wrong. I just want to understand the carb operation more. I obviously need more knowledge about it. I really appreciate it guys.