Black 84 Z

I have a 650 DP carb on my camaro. It has run alright (not necessarily good) for quite some time now. Since it is not my DD and can only drive it on the weekends (antique tags) I have not taken it to my local shop to get tuned properly, I just live with an uneven idle and the gas smell on startup. Today I tried to fire her up and the starter wouldn't turn it over at first almost like it was hydrolocked. After a couple of attempts I got it to turn and it did run, but incredibly poorly, if I took my foot off the gas it would die almost instantly. I managed to get it backed out of the garage and up a portion of the driveway before it died again. My driveway goes uphill from the garage to the road so it was parked with the front pointing down. I opened the hood and took off the air cleaner to find fuel dripping into both of the front barrels. I limped it back into the garage where the floor is level and I couldn't see any fuel dripping but the was definitely a vapor in the front barrels.
I have a couple of questions for the board:
1. What specifically would cause the leaking?
2. What would fix the above problem? I'm guessing a rebuild would likely be in order, but want to be sure.
3. Having never rebuilt a carb (or even really tuned one) before, how easy/difficult is it and what should I use as a reference if I attempt it?
4. If this was going on to a lesser degree before, would it cause the bad idle, smoke on startup, strong gas smell I had before?
TIA guys!!!

sofakingdom

iTrader: (1)

1. A leak. Most likely the front power valve, especially if it has ever backfired.

2. A rebuild. Which of course includes a new PV.

3. A Holley carb is probably the easiest sub-assy of a car to rebuild. It's one of those things where if you can't do it, you need to find a different hobby. There are any number of good Holley books out there. For tuning, follow the "sticky" at the top of this forum.

4. Possibly yes.

Black 84 Z

Mentioned this problem to another friend and he thought it could be stuck float. Is that a possibility as well?

sofakingdom

iTrader: (1)

Not really; that would cause the carb to spew fuel nonstop whenever it's running, and you'd probably have fuel literally pooling on the intake and running off and dripping from the engine.

But trash in the needle could do this.

However the most likely cause is probably a ruptured power valve from a backfire.

Problem is, to get to ANY of those things to fix it, you'll ruin a couple of gaskets, for which you'll need new ones; and if the needle valve or the power valve itself is bad, you'll need a new that; and if that doesn't fix it, you'll need a new ... whatever else, and so on. So no matter how you slice it, if the carb isn't a FRESH rebuild already, you might just as well tear it down and renew it; otherwise you'll fix this ONE symptom, maybe, if you're lucky;and tomorrow there'll be something else fail, and the day after that, and the day after that.... so unless you just really like dinking around with your carb, best to just shotgun the whole thing and put it behind you.

mmadden55

Any number of possible causes but holley rebuild is cake. Get the kit usually includes step by step instructions. I was a hs sophmore when I did my first on the kitchen table. Took about an hour. Recommend getting a stell bucket big enough to hold the whole carb and a gallon of carb cleaner. Pour the carb cleaner in the bucket submerge the carb in it and let it soak overnight. Makes the rebuild so much nicer and easier.

Black 84 Z

Thanks for the replies guys, I had already figured on the rebuild regardless mainly since I was going to be tearing it apart anyway might as well do the whole darn thing and be done with it. If nothing else it will give me a chance to learn a little about the inner workings.