Fuel leak on my 1970 Charger R/T 440 4bbl

[B5ChargerRT]

Hi, I have just signed up to this forum. I have an issue with my Charger and would greatly appreciate any help/advice.
I purchased this newly restored car a few months ago. Everything was great, took it out for a number of rather short drives - no issues, and it started perfectly all the time - until I took out the longest ride yet, about 40 miles (incl. 10 miles at 75MPH) about a week ago. It almost used a half tank of gas for the roughly 40 miles, which I thought was a lot, even for a 440. On the next day, I had a hard time starting it. It did not idle fast after cold start up and white smoke came out of the exhausts. It also appeared it wasn't running on all cylinders. One of the old sparkplugs was loose and almost came off by itself, another one was wet of gasoline. So I purchased a set of 8 new NGK 3332 XR5 spark plugs and installed them. I started it up (it took a while) and white smoke, followed by a lot dark smoke and dirt/grime came out of the exhaust, then the engine stalled. I pushed it out of the garage and started it up again, and managed to have it run 90 seconds before it stalled again (again white followed by dark smoke). Then it wouldn't start again. I took off the air cleaner, and have then noticed a pool of fuel sitting next to the carb. I also thought the choke may be stuck because it stalled all the time, but I don't think that was the case...  When the car is not running and I push down the accelerator, fuel slowly starts to drip (and when I start it up, the dripping gets faster and faster) - see image. In any case, I was wondering if anyone has an idea why the fuel suddenly leaks at one/two or even more places (or perhaps it has leaked before but to a much lesser extend and I didn't notice), and if this leak is also the reason for the white and dark smoke, and that the car does not idle fast after cold start up.
Thank you,
Jakob.

[UFO]

That looks like silicone squishing out. There's a gasket there, never silicone.
Do you have a spare carb to install? Maybe borrow one from a buddy.
Half a tank  to go 40 miles is a major leak.

[Pete in NH]

Hello and welcome to the group,

How did the old spark plugs look when you took them out? Where they sooty black and wet with gas? It sounds like the carburetor is flooded with gas. Could be anything from a improperly set float or floats , defective floats or something wrong internally with the carb. I'm sure some others will reply to your post and it would help to know what type and model of carburetor is on the car.

The black smoke is too much fuel I'm not sure about white smoke though, I've always thought of that as burning antifreeze or water.

And I agree with UFO, I've never seen silicone RTV used on a carburetor as a gasket. I'm not sure it would hold up long term in gasoline.

[myk]

Yup-if that's silicone then the 'carb will have to come apart so that a proper gasket can be installed.  As for everything else, Pete's got it covered...

[B5ChargerRT]

Hello and welcome to the group,

How did the old spark plugs look when you took them out? Where they sooty black and wet with gas? It sounds like the carburetor is flooded with gas. Could be anything from a improperly set float or floats , defective floats or something wrong internally with the carb. I'm sure some others will reply to your post and it would help to know what type and model of carburetor is on the car.

The black smoke is too much fuel I'm not sure about white smoke though, I've always thought of that as burning antifreeze or water.

And I agree with UFO, I've never seen silicone RTV used on a carburetor as a gasket. I'm not sure it would hold up long term in gasoline.

Thank you!
Here is an image of the old spark plugs. The first one was the loose one, it seems to have some burn marks. The next was a bit wet with gas, the third one was quite wet with gas. The others were not wet, but as you can see quite black... The engine itself was rebuilt in 2013 (I have the receipt for that), and it ran beautifully until the fuel leak last week. but some douchebag put in the old sparkplugs in, which the original owner purchased in 2003 (I also have the receipt for that.). Not sure why someone would not spend $20 on new sparkplugs, when they just paid $6k for the engine rebuilt. Perhaps the same guy that used the silicone instead of the gaskets. I need to check regarding the carb model, I'm not an expert. Any idea whats the best source for a set of gaskets for the carb? Thanks again, it's greatly appreciated.

[Pete in NH]

From the looks of those plugs, your engine has been running a rich mixture, so there are some carburetor issues for sure. As to the carb. model if you are not sure and can't find an I.D. tag on it, the easiest thing to do would be to post a picture with the air cleaner off and I'm sure someone will be able to identify it.

If there really is silicone RTV in there, the carb will have to be torn down and completely cleaned and rebuilt properly with new gaskets. Depending on the type of carburetor you should be able to get a complete gasket and rebuild kit from a number of sources.

[B5ChargerRT]

more images to follow

[B5ChargerRT]

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[histoy]

You may also have a problem with excessive fuel pump pressure that is overcoming the float / needle valve and seats so that the carb floods.   I've had to install a fuel pump pressure regulator on  several of these Carter and Edelbrock carbs.   I even ran one for my 426 Max Wedge carbs.  I've found that 4 1/2 to 5 lbs. has worked well.   

[Pete in NH]

Looks like a stock Carter AVS series. You might have a small metal tag with a carb. I.D. on it. The number will be some thing like 46XX with the last two digits identifying the carb. for an automatic or standard transmission. The whole number would be something like AVS-46XX. I don't have a factory service manual for 70's. For 1969 the numbers were AVS-4617S and AVS-4618S For example. Rebuild kits are readily available for those carburetors and they are fairly easy to overhaul. Having the carb. number will ensure you get the right kit.

[UFO]

Carb number should be stamped on the front near the mounting hardware.

[B5ChargerRT]

A0 4737S

[UFO]

Correct number for a '70 440 4spd.
Leak from the throttle shaft can be fixed.There is a bushing that get's installed.Never done so I am not sure if it's a do it yourself thing.
Is that silicone? Or does it just look like it?

[B5ChargerRT]

doesn't look like a gasket