Hey all

My next project on my 67 bird is dealing with the Rochester Quadrajet 4bbl carb. I plan to rebuild it myself, but have never done it and I know I am missing a spring or 2. Because the 'air valve' for the front 2 barrels is flapping in the wind. Also, there are some plugs on hoses/ports that I am not sure should be there. There are a few books out on it, but in reading reviews, they all have some faults. Anyone have a favorite book, method, or some pictures of their carb they can send me? Also, I know this will be a meticulous job, but how reasonable is it to do, and how hard is it to tune the carb? So really any helpful info you have on this would be great. I am just getting into the whole rebuild, so my experience is limited.

Thanks!

Ben

Cliff Ruggles' book is a must. A straight rebuild is fairly uncomplicated, but two things you should do in my "opinion" are, re-bush the throttle shafts and epoxy the bowl plugs(if they haven't been done in a previous rebuild). All is covered in his book.

One other thing on the for sure to do list would be to make sure the secondary throttle plates fully open. There's alot of power to be gained and it doesn't cost a dime.

Good point Bob!

thanks guys! I'll be back if things go awry. And they likely may...

More to come, thanks!

Ben

The flap on the front two barrels is the choke. The flaps on the two larger rear barrels are the secondary air controls.

Chances are you are missing some or all of your choke hardware. If you post a photo we can help you with it.

I took some pictures but can't figure out how to post to show you guys. Looks like it wants a weblink. Any ideas on how to add pictures to a post from my PC?

Ben

Click "reply" then file manager. You can then select photos for upload to your message.

Ok here are the pictures. one from each side, and one from the top. Like I said, the primaries flap in the wind. I just bought a rebuild kit and the Cliff Ruggles book. Hopefully that will help, but can you tell what is missing? Looks like the passenger side is missing a spring maybe. Not sure though.

Thanks guys. This forum helps out a lot.

Ben

Well...for starters, it's not a Pontiac Quadrajet, at least not a V-8 model. The fuel inlet is straight in from the front for a Pontiac V-8. That's likely why the choke is not attached, Pontiac used a well choke and other makes used different designs.

You have options, though. You could add a manual choke cable. You could fix the choke in the open position. You could find a more compatible carb. You could take off the choke blade.

The choke is not essential for operation. Many on this forum don't even run a functional choke. I do like having a choke, but as my heat riser ports are blocked off I had to swap parts to get it to open properly.

First step would be to identify what carb you have. Cliff's book will tell you what you need to know. All Quads are very similiar in performance once tuned to your needs. I would check the travel of the throttle with the pedal linkage to be sure you are getting full open throttle when the pedal is fully depressed. Check this with a helper, with the engine off. Have the helper depress the pedal, then see if you can open the throttle more by hand. If you get an additional 1/4" or more of travel, you will need to adjust your linkage.

The photos are of my '69 QJ. There are a few differences, mostly throttle cable and automatic kickdown, but the choke side is the same.

rebuilding the carb is not hard just dont lose anything and start slowly. do not remove the butterflies on the base of the carb they are precision set. doing so will cause leaks of air/fuel. when you clean it up make sure that the small holes are blasted with air to blow out dirt. get a new float also follow the level instructions for that carb number. it looks like a newer carb possibly not correct for the firebird engine. once you assemble it don't over torque the screws it will strip out. the choke rod and set up is the worst part to assemble because they have to be manipulated together partially in the carb and its tedious so say the least. make sure the float is installed correctly and the fuel filter is in the right way. also the previous owner might have rebuilt it using the wrong gaskets so check to see if they are correct for the carb. one tiny hole can be hell. thats it should be ok. good cleaning, paying attention to instructions and patience is the key.

If you look at the pass side of the choke plate you will see a rod going down into the carb casting. At the bottom of the rod there is supposed to be a piece with a square hole that the choke pulloff stem fits into to operate the choke lever. More than likely some one removed the pulloff at some point and didn't put the square peg back into the square hole. It's not easy. That's why the flap flops.