Holley 600 question

[FUTURE_OF_GM]

Okay, so here's the deal.

I run a Holley 600 on one of my Camaros. Every week or so this winter I would go out and idle the car to keep everything in good shape, but the car hasn't been "on the road" in a year or so.

I got it out the other day, everything seemed fine, and changed the plugs. With the new plugs in I fired it up and it purred like a kitten. I put it in gear and tried to make it to the gas station but ran out of fuel at the bottom of my drive. After adding about 3 gallons of fuel, the car started this thing where it wouldn't idle. I figured it had just sucked something up into the carb or fuel filter. So, for good measure, I added some fuel system cleaner, replaced the fuel filter and replaced the PCV filter all to no avail. The next day I got in and fired it up because I was going to spray some carb cleaner in, but the car idled fine. "Problem solved" I thought, "I guess it just sucked soming into the carb and now that 'something' has dislodged and burned."

Then I made the mistake of putting the car in gear. It started doing the same thing; struggling to idle like it's not getting fuel. I took my chances and decided to go for a ride anyway. I figured I'd air the carb out a bit and try to clean out the cobwebs. I cracked open all four barrels at least 3 times and the car runs absolutely great as long as I've got my foot in the gas. But as soon as I take my foot off, it dies and wont even idle. It also flooded out on me one time while I was out (So much for those new plugs, eh?)

So what the eff is wrong with my carb? (Besides the fact that it's a Holley) I've never really messed with carbs much but I'm thinking either the idle is too low (it's cammed and idles around 5-600 rpm) which i doubt or something is wrong with the float levels/choke. Anyone know how I can fix it? (Keep in mind that I haven't messed with carbs tht much)

Edited March 5, 2008 by FUTURE_OF_GM

[Camino LS6]

Sounds like a vacuum leak, FOG.

In cars with carbs, the downtime can allow the gaskets to dry out and shrink allowing leaks to happen. There are many other things it could be, but I'd start by checking the tightness of all screws holding the carb together. The second thing I'd check is all vacuum lines to see If you have a leak. Third suspect would be a stuck (or sticky) float valve.

Hope it's one of those.

Edit: does it hesitate when you give it gas? If so, the accelerator pump could be shot (they can dry-out too and don't come into play at idle).

[FUTURE_OF_GM]

As far as I know, no hesitation. And the reason I say it that way is because I haven't really been able to pull off from idle. As it is, I have to throttle the car up a bit and drop it into gear so it kind of 'hits the ground running' so to speak.

I suspected a vacuum leak as well, which I'm not at all thrilled about. I'm really hoping that it's a float.

On a related note, it felt amazing to be back behind the wheel of my baby after it spent a year waiting on body work.

Edited March 6, 2008 by FUTURE_OF_GM

[Camino LS6]

Well, there is an easy way to check for vac leaks: Just spray a little gumout or similar product on any suspect area and listen for a change in RPMs. If the RPMs change, you have found a leak.

I'm no expert, but I've rebuilt a few carbs over the years and struggled to make a few Holleys run right - so if you get stuck PM me for my cell # and I'll try to help you out if I can.

Oh, just a thought, you may want to check the vacuum advance on the distributer - you may not have a carb issue at all.

[SuperSport623]

i can tell you a vacuum leak gave me the same problems on my old quadrelet on the old motor.... so Camino might be right....

im trying to figure out how to tune a freaken carb.. i have an Edelbrock and i have no clue how to make any adjustments like jet size and swapping accleerator pumps... the more i try to figure out what to do, the more confused i get

[Camino LS6]

i can tell you a vacuum leak gave me the same problems on my old quadrelet on the old motor.... so Camino might be right....

im trying to figure out how to tune a freaken carb.. i have an Edelbrock and i have no clue how to make any adjustments like jet size and swapping accleerator pumps... the more i try to figure out what to do, the more confused i get

That's one of the reasons that I want Project Camino to have EFI. I love old cars, but carbs are a PITA.

[SuperSport623]

oh yeah they are.. i like the idea of being able to load a tune onto a ECM then having to figure out carbs.... my timing is dialed in well, but with my carb running weird, it doesnt help

[Camino LS6]

oh yeah they are.. i like the idea of being able to load a tune onto a ECM then having to figure out carbs.... my timing is dialed in well, but with my carb running weird, it doesnt help

Believe it or not, I always tuned my carbs "by ear". I could get them running great, but the next week they'd need attention again (especially Holleys).

[FUTURE_OF_GM]

i can tell you a vacuum leak gave me the same problems on my old quadrelet on the old motor.... so Camino might be right....

im trying to figure out how to tune a freaken carb.. i have an Edelbrock and i have no clue how to make any adjustments like jet size and swapping accleerator pumps... the more i try to figure out what to do, the more confused i get

I run an Edelbrock on my other Camaro and I would highly recommend it over the Holley. It's not nearly as tempermental.

Believe it or not, I always tuned my carbs "by ear". I could get them running great, but the next week they'd need attention again (especially Holleys).

LOL. Reminds me of what an old timer said to me one time. "Adjust that Holley today, romp on it once or twice tonight and then repeat the process tomorrow."

[SuperSport623]

ive heard that so much about holley's.. i hear once you get an Eddy tuned, it usually runs great and stays that way.. but im gonna have to figure out what im doing.. i taught myself how to set timing a few weeks ago, and i guess ill figure out how to do this... gotta learn somehow!

[Camino LS6]

[A Horse With No Name]

Old gas will do that also. The lighter Hydrocarbons seem to evaporate and cars that are stored seem to run like crap for a tankfull or two until the old gas is all the way out of the system.

My Chevelle did that, and my 55 Chevy did that also.

Chris