carb model

[Stewart G Griffin]

i have no idea what the difference is (if any) between a 305 and 350 q-jet, but my 83 originally came with a 305 and got swapped over to the goodwrench 350.

The carb # is 17083224.    i am presently using a 2GC because it came with the 305 i am using now.


2) For those that recommended an SMI unit, would going with a Cliff Ruggles unit also be a good recommendation?

[454Man]

Cliff is an awesome dude... He even has his own forum. :-)

What's under the hood??? If you have to ask maybe we shouldn't race...

[cwilson jr]

my q-jet is not computer controlled, but it is one of the ones that have a couple of electronic sensors on it from 85-86.  i have one electronic component on the top front left of the carb. (when looking under the hood).  after doing research it looks like it is a mixture control solenoid?  and believe it had something to do with the old esc system?  and i no longer have esc.

there is also the idle speed control valve in the front right.  i would think this still serves a purpose, even though mine looks rough and i'm not even sure it works.

do i need these at all?
for the moment, before i can order one off sean, i'm cleaning mine the best i can to use it for the time being and would like to remove/do away with anything i can.

[jason]

Here's a couple tips I can give you seeing as my truck was just sitting on the road dead for the last 4 months. 

I just got it running again and after having rebuilt my quadrajet about 4 times due to stupid mistakes...

I can tell you that rebuilding a quadrajet is actually SUPER EASY.

If the carb is dirty that's your first problem.  A dirty carb might have a constricted orifice.  This may be restricting flow.  All it takes is 1 tiny piece of debris in your idle pickup tubes to prevent your truck from starting.

A quadrajet is vehicle specific.. but I bet a 305 quadrajet will flow enough air and fuel to run a 350.  You could most likely tune it to run your 350 quite well.

If your carb is dirty just take a camera, organize your work area, and and start tearing it down.

Youtube has an EXCELLENT SERIES OF VIDEOS ENTITLED "how to rebuild a quadrajet" by "whosaidtyler".  It's a very involved set of videos... the total length is something like 4 hours because he goes through each step of the tear down and rebuild process.

Soak the carb in a bucket of carb cleaner (making sure not to soak rubber or plastic components if possible). 

IF you have compressed air.. after letting it sit for a couple days then blow out all the crap from each orifice.

re install with all new gaskets, accelerator pump, etc.  You should be golden.

If you try to find a "new" carb you run the risk of getting a carb that "could' have warped sealing surfaces.  Check your sealing surfaces with a square and verify it seals well.  IF the edges of the carb are square (a few mm isn't a big deal).  Then you should be fine.

There really isn't much to a carb.  Setting the float however is a task.  You set that up wrong and your carb will blow gasoline all over the engine. 

When you measure you measure across the little plastic line on the float.  The videos on you tube are very clear, and concise. 8-11/32 of distance between float and top of casting is a general rule of thumb I'd use.  Some other people have mentioned to have the float closed when it is flush with the top of the body of the carbs casting.

You could rebuild a carburetor in an afternoon, granted it was soaked and cleaned well.  That's THE CHEAPEST, EASIEST ROUTE.  Trust me.. the feeling of satisfaction will be worth 10,000.00 when you can tell people "yeah I rebuilt and tuned my carb". 



One last thing>  most mechanics nowadays don't want to deal with carburetors.. which is stupid because they are so simple.  I was stressing over my quadrajet recently... but they are very user friendly.

Last thing>  when tightening the bolts in the carb.. and connecting the carb to the intake manifold.. use A LIGHT TOUCH ON THE BASE GASKET.  Those are the only tips

[jason]

also: to the question what's the difference between a quadrajet that is egr compatible or not egr compatible?

EGR: Exhaust Gas Recirculation.  The EGR is just a little vacuum controlled actuator valve that controls exhaust gases being sent back into the engine to be burned again (if i'm not mistaken).

That valve is controlled by a line that originates at the carb. 

The difference is just that there are less vacuum hoses and your vehicle is now equipped to permit more smog from the tail pipes.  Reason being is the egr no longer exists so there is no need to run a vacuum line to control it. 

The carbs are virtually identical.  I used the exact same quadrajet after deleting my egr.  The EGR is just wasted space anyway.