Need a carburetor lesson

[Akodo]

OK, I recently bought my dads 79 Trans Am. I have owned carbureted cars before, but it was YEARS ago, and I never had to tune them. This one, the choke doesn't seem to work, the idle is WAY off, and it tends to drop the idle as it warms until it dies out. What I need is someone willing to spend an afternoon teaching me whats what on the carb, which screws do what, how everything works, that kind of thing. Or if anyone knows where there is a good tutorial online? I could send it off to have it done, but i want to learn how to take care of this thing myself. I will of course supply the beer, pizza, etc.
As far as I can tell, its the stock Rochester that came with the car.
5engine.jpgcarb 1.jpgchoke.jpgvacuum lines.jpg

[landstuhltaylor]

I've been following this for my bike: http://katriders.com/vb/showthread.php?t=131010

I'm sure your carbs are very different but the general components should be similar. If the car has been sitting a long time I would just go ahead and pull it all apart and clean/inspect it. You can count on the idle jets being clogged.

[SOPES]

Those old rochesters are great once adjusted right, But I second the pull it off and clean it up idea. Prolly got all kinds of gunk in it

[TB2]

Sounds like definite choke problems. If that carb hasn't been apart in a long time, i'm sure the accelerator pump is shot. Where you located?

[TrickyTransAm]

Lovely hot air choke on that one. You may strip the threads on the choke body when removing it. Spray it down and take your time.

You can do two things...
1. Buy a kit and go through the carb
2. Buy a reman'd Rochester Quadrajet ready to go, then dial it in. You can buy a performance calibrated one, or have yours modified. I believe there was a gent. in Illinois or Indiana that specialized in Rochesters.

They aren't too awfully bad to refresh yourself. Usually the kits come with instructions, or you can get a Quadrajet book on Amazon for fairly cheap that explains all about each model. If you look at the bottom throttle plate, there should be silver caps over the adjustment screws if the carb has never been adjusted.
There's also a special tools to dial these in, which are probably now fairly cheap on Ebay.

Rochester carbs are an excellent choice and not terribly difficult to tune. I'd take a dialed Rochester over any Edelbrock Anyday - even if it was a 2bbl. Holley would be the only other alternative, but you'd have to re-route vacuum lines, etc etc... not worth it unless your swapping manifolds. If you do, check the casting number of the manifold before you do, since some of the Olds and Pontiac Manifolds flowed quite a bit of air - Some equal to aftermarket ones.

Looks like the fuel line nut got the Vice Grip treatment. I'd replace it. Reference Inline Tube PFE7902

Books for reference: HPBooks - Rochester Carburetors ISBN#0-89586-301-4 (own it - very helpful)