[Bad66]

Well my Buick has been kicking my rear this year. For some reason my new (only used about 6 months) holley carb is acting up. When I'm in park and i give it the gas real fast, it stumbles and there is a loud clap that comes from the carb (like a white mist). I have also seen a little gas come out of the vents. If I ease into it, it's fine and revs smoothly all the way up.

I have checked all my vac lines, plugs, wires, timing...etc. I did not have this issue until after I pulled the engine to fix the oil pump. I had removed the carb and it sat on my workbench for about 4 months. I whent through the carb, everything is fine. I pulled the site plug on the primary and a little gas came out, I shook the car and gas came out . Any ideas? It's a chevy 350, and the carb is a holley 750 w. vac secondaries.

[gofastz]

did the power valve check good? and what kind of gas are you useing? the new gas with 10% ethonal can eat up rubber parts in carbs, i found its best to stay with 100% gas!

[Bad66]

Originally Posted by gofastz

did the power valve check good? and what kind of gas are you useing? the new gas with 10% ethonal can eat up rubber parts in carbs, i found its best to stay with 100% gas!

Yeah all gas and the power valve is good, I turned the mixture screws and the engine died

[bracketeer]

If the carb has been sitting for over 3 months your pump shot channels in the bottom of the float bowls are plugging up. clean out with piece of guitar string.
if not, popping is a sign of leaning out. problem will be with pump shot squirters. put bigger ones in.

basic holley adjustments. set floats with carb on engine. set mixture screws 1 3/4 turns out from bottom. jetting is done by looking at the porcelain part where the electrode protrudes out of plug. color should look like dirt. black jet down. white or grey jet up. 3 sizes for either. next comes squirters. popping need larger. bogging need smaller.