Pig rich

[bkcole2]

My suburban runs pig rich all the time and smells like a gas station anytime ut is turned on. Its to the point that my wife can smell it on me in the house after i drive it. Its getting old fast. I pulled a plug and it is very obvious its running rich.

Its a 350 goodwrench motor and it has a edelbrock avs 2 carb. I supposed the first place to start would be changing the metering rods. The carb is currently as it left the factory. I have 5.5 to 6 psi on furl pressure and the electric choke is opening properly. Is there anything else i can look at to help remedy this?

 

[1-ton]

Check to see if the float bowl needle seat does not have dirt in it, which is allowing excess fuel to pass through the carb.

 

[Chickntrk]

How does it run? If it smells that bad it seems like you may have unburnt fuel leaving the combustion chamber, to me that looks like a plug that hasn’t fired in awhile, when was the last time this thing had a tune up, what’s the timing set at?

 

[Wes Harden]

Need to check the primary venturi are not dripping at idle. If you have dribbling out the venturi, some adjustments might solve that. Close the throttle plate with the idle speed screw. You may be able to add idle rpm with the air fuel screws and timing. Adjust the air fuel screws for best manifold vacuum, and if needed advance the dist timing.
If these adjustments don't help time to get a jet kit and re jet the carb, Edlebrock's are fairly easy to jet

 

[bkcole2]

I cant see any dribbling of fuel at idle. The truck drives great other than stumbling when you step on it. The coil cap wires and plugs are all new with less than an oil change on them. I have tuned the idle with a vacuum gauge. If my memory serves me correctly, I had about 17” of vacuum at my best idle. I have tried a few different timing setting with my new heads. Currently I believe it has 12 degrees advance at idle. It smells rich at idle and while driving. I pretty well know its got too much fuel but thought maybe I might have an evap problem or something along those lines.

 

[Wes Harden]

Do you still have a charcoal canister? They certainly help with fuel orders in the garage

 

[6872xtc]

What is the elevation where you live?

I am at about 4700' and what I did with an Edelbrock 600 was to swap the jets from the secondaries into the primaries, then get larger jets for the secondaries. With their original series carbs, they were rich on the front, lean on the back right out of the box.
I had 107 jets in the secondaries of my 600, which made it run pretty good. It actually sounded close to a Q-jet at WOT.
Next to check is the step-up springs. I run either the blue or orange, which are the softest ones. Keeps the metering rods from raising too soon. I used the blue ones for a truck with an automatic transmission, orange for the manual transmission truck.

 

[bkcole2]

Yeah its there but i bet its not hooked up right. There tons of fittings with nothing on them. I leaned out the carb two stages in cruise and power mode. Me and the ole lady took her for a test drive to the ice cream shop and i pulled a plug when we got back. It’s shown below. I will probably have to get a fresh set to tune it any with the plugs but it looks leaner for sure, maybe too lean. While driving I got it into the secondary and it was proceeded by a strong gas smell. I also changed the springs that control when the primaries go into power mode to the max 8” vacuum spring. (Factory was 5”) still has a bit of a bog when getting on the skinny pedal but it does seem improved. I may need to cut back the secondary jets too. My squirter is in the hole closest to the carburetor, which should be the smallest shot. I also reset the idle and got it to 18” of vacuum of idle at an 800 rpm idle. I checked the timing it was at 13 degrees at idle. I adjusted the timing down to 8 degrees at idle. When I hook up the vacuum advance i have 20 degrees at idle. My timing is at 32-33 degrees total all in at 3000 rpm. I think I am gonna drive the truck some more and see what I think about it before I do any other changes. I probably have done too many at one time. I also have a nagging thought in the back of my mind that I should have replaced the the timing chain set when I did the heads and cam. I just don't feel like the engine is as peppy as it should be even if it is in a suburban. I fear the factory chain in the gm goodwrench motor may have the cam timing retarded. I did not check it so I have no way of knowing without tearing the engine down.

Any help is appreciated.

 

[bkcole2]

Im in alabama and the elevation is about 500’ here