When I rev my engine It will put out a good amount of black smoke. It just started doing this what could the problem be?
I just put a new carb on so that might have something to do with it, but I don't know how that would affect it.

 

yeah shes runnin a lil rich,check that a/f mixture,when was the last tune up?

 

yes, your carb needs tuned, or smaller jets or something. black smoke = fuel.

 

Ok well it's a rochester quadrajet and I don't know how to work on one of them. How do I adjust the air fuel mixture? Would that be the the 2 adjuster screw type things on the front of the carb? I thought those were both air... And if that's what I need to adjust how many full turns should they be turnded out?

 

Qjets adjust fuel by rods and hangers. Most carbs, like Holleys, use jets.

 

What is a rod and hanger? Can I adjust the fuel with the 2 adjuster screws on the front of the carb? Or is that just for air?

 

The metering rods are on the top front of the carb directly in front of the priimaries theres a little oval looking cover on them you pull off. Q-jets are a little difficult, one adjustment throws off 2 others.

 

So how should I adjust them? Any certain specs or anything I should know?

 

When I look down into the jets I see two little hex nuts down in there or that area are those something I need to mess with?

 

If I understand right, the way rods and hangers work is like this:

There is a hole (like a jet i guess) that fuel passes through to be sucked into the engine. Now, obviously an engine does not need the same amount of fuel all the time, so there much be a way to richen up the mixture and lean it out, right? This is where the rods come in. They are a long rod that is tapered to a point at one end. This pointed end goes into the 'jet' hole to restrict fuel flow. As fuel demand goes up (ie. opening the throttle) the rod moves away from the hole to let more fuel in. This is where the hangers come into play... the hangers are what pull the rods away from the holes. Different hangers will pull out the rods different amounts and at different rates. Different rods have different 'tapers' at the ends to change flow rates.

Now, I haven't taken apart a Qjet myself, only Holley carbs, but this is the way it was explained to me.

 

I'll have to wait for my brother (berlinetta kid) to get home. He might understand this stuff.

 

so we'll need a jet kit? do the screw on the front only adjust A/F ratio at idle like on an edelbrock? Anyone know any tricks we can do until we can ge ta jet kit if it's needed?

 

The screws you refer to s/b the curb and fast iidle adjustment screws on the botton right side of the carb (under the choke pull-off vavlve).

The other reply is on the money with the hangers to adjust the flow rate. When you get a rebuild kit, there is a I think 2 or 3 sets of hangers to meet your carbs needs.