First off I'd like to give out a quick thank you to everyone here on the forums for the wealth of information and great community here. I've been reading many many posts learning and gathering info since about 4 months ago I made my first corvette purchase, a 1980 4spd with 57k miles in original factory condition parts wise. Other than a little under the hood neglect it's a great car. Without the very knowledgeable people here I could never have learned how to fix the problems the car has had or properly rebuild what I have.




Now onto my current problem...

Since the cars upper end was essentially dirty, wore out, with vacuum leaks, horrible valve cover oil leaks and neglect I opted to replace everything above the heads as well as delete all of the smog related equipment besides PCV. Just a quick run down on the mods made in case it has any bearing on my issue:

Smog delete/Exhaust replace with Hooker Comp Headers
New Carter Fuel Pump rated @5.5-6.5psi per the manual
Braided Stainless Steel Fuel Line
Edelbrock 2701 eps intake manifold
Edelbrock 1406 carb (eventually want to have my Q-Jet rebuilt by a PRO who knows what the hell he is doing)

Got everything finished up a couple days ago, dialed the timing in, got her fired up and was feeling great about all this hard work paying off. Then shortly after I discovered my carb is leaking fuel at the base between the carb and the manifold. I used an edelbrock plenum heat spacer to avoid any potential fuel boiling/heat issues and the fuel is leaking and pooling onto the manifold on the back left corner of the carb if you were facing it from the front of the car. What I'm wondering is the carb flooding and leaking? Or is this just a seal issue? I dont see any damage to the carb and it is torqued to spec. I'm concerned about flooding because I definitely dont want fuel leaking down the cylinders and into the oil. I'm not running a fuel pressure regulator or anything but I wouldnt think the carter fuel pump would be anything too crazy, its basicly a stock replacement. I plan on double checking the floats shortly to make sure they are correct. The carb is as is out of the box, no adjustments made to it. It idles fine and has no issues accelerating up to 4k rpm with no signs of roughness or sputtering. Any tips on how I can be for certain if this is a flooding issue and how to determine why it is leaking? Thanks for your help, I really appreciate it!

 

Yeah my 1406 was a leaker too.When the car is running just at idle, look down the primary and see if fuel is dribbling out of the boosters? If it is, the floats are too high or there is something in the needle and seat.Easy carb to get the top off, make sure all the screws are tight when you put it back on.

 

I will check on that as soon as I can spend some more time on the car. If it is just leaky is there something I can use to help seal it? I know most gasket makers + gasoline on a carb is a no no. I think I will also pull it off completely and take a close look at the base to see if its possibly uneven or has some burrs to sand off. Then try some fresh thicker gaskets.

 

Does it leak with the car running, or does it leak after you shut it off?

 

It appears to only leak while running. The leak stops when its shut off. And it only leaks and pools on the one side.

 

ok you should be able to trace the leak while its running.

 

Double check to make sure you have a flat steel washer on both sides of the fuel line banjo fitting where it hooks to the carb. you will have a yellow stain on the carb from where it leaking as well.

 

Watched it real close while idling and found 2 sources of leaks. First the banjo fitting was dribbling a very small amount of fuel. I put the washers on right but apparently it needed a little extra torque. That leak stopped. Second the base corner leak continued so i pulled carb and found the base had a small burr in the corner left over from the casting process id assume. I lightly filed it off and retorqued the carb and so far so good, no leaks at present. The boosters are also not leaking any fuel at idle so appears to be operating normally. Thanks for your help and insight grumpy427!

 

your welcome, glad i could help.