Rebuilding my carb and have not ran across this before it’s a extra set of louvers in the carburetor can anybody tell me how these work there is no linkage to them and they have a light weigh



t spring do they work on vacuum coming from the intake?

 

What type of carb is that one?

 

Never seen anything like that

 

air doors, similar to the back ones on a q jet. pulled open by vacuum

 

Yes, it is a Quadra jet 4GC it is off my 1962 Oldsmobile 98 and I just figured out Daytona parts sent me the wrong gasket kit

 

First time getting into a four barrel Quadra jet last one worked on the two Barrel never seen the extra **** of flap in there. Thought I would ask.

 

It is an auxiliary throttle valve and is supposed to have light spring tension. I'm guessing and don't know for sure that the spring tension is overcome by airflow like the air valve on a Q-jet. Read that early 4GC's didn't use them, they came in around 56.

Hopefully another member knows additional info.

 

Yes, ATV. Attached (to this Post) is your very own digital 4GC Service Manual. Open the .pdf, search for the term/text auxiliary & note 10 instances describing application of the ATV.

 

It is not a "Quadrajet" it is a 4-jet Rochester. Big difference when you are talking to people about it.

 

could explain why I got the wrong kit. For some reason I was thinking that were the same. I’m guessing the type I was thinking it was is a later version of the one that I got?

 

Totally different animals. There should be a tag on your carb with the carb number unless somebody has taken it off in the past. There are a bunch of different variations of the 4-jet so you really need to know which one you have before you order parts. Not sure where you are getting parts from but Mikes is where I have gotten kits in the past. They can probably help you figure out what you have if you dont have a number.

https://www.carburetor-parts.com/4-jet-carburetor-parts

My experience has been they are somewhat tricky to get setup and working well

 

Someone has already been in the carburetor before. There’s no tag on it. That’s the first thing I looked for when trying to order the kit. I had remembered reading about the tag in a post or somewhere before, but for some reason it didn’t don on me the difference between the 4 jet and the Quadra jet. I ordered the kit from Daytona parts and gave them the make and model and engine size.

 

As per Bill, if the tag is no longer attached to the carburetor, clean each corner of the top of the carburetor - you may get lucky.

 

Mike has a YouTube series demonstrating a 4-Jet rebuild. Here is Part 1. Good Luck.

 

Actually, that’s the guy I watched for this rebuild, but he’s working with a little bit newer of a version of the 4 jet.



This is from another video. This carb is closer to what I have except he has the round shape float and I’ve got the rectangle shaped float

I’m thinking one of those two are going to be what I’m looking for.

 

If there is no carb. Model Tag, & no numbers on top of the carb. call Mike for assistance in evaluating.

 

Called and talked to the guy that I got the kit from and it is the correct kit. The slots on the gasket in between the lower louvers and the fuel bowl are meant to be there. The one I was looking at, the one I watched was for a marine application, which don’t have. They’re there to provide intake when the engine is hot. I did not know this, I do not have the book for it, I’m starting to think I need to get one lol. Otherwise, it would’ve explained it in the book, but got the carburetor on. Got it to start. Need to do some adjusting however it started to sleet and snow here. So going to do it when the weather gets a little better. Thanks for all the help and support.

 

Download attachment Post #8 (above) #8

 

oh thanks, I did not notice that earlier. Will definitely be doing some reading. 😀

 

I am a complete novice on any 4-Jet carb. I've provided assistance in rebuilding a couple - that's the extent of my knowledge. My first car (1969 purchase) was a 1967 4-4-2. Any deep-dive familiarity I gained from working on Quadrajet models; therefore, it's doubtful I'll be able to provide any deep-dive assistance w/ a 4-Jet. Other CO members will hopefully have more knowledge. The 4GC document (attachment) I posted has an excellent description & tuning section. I resided in Norman, OK five years (grad school), 1984-1988. Stay indoors - it looks damn nasty. Good Luck!

 

Most definitely staying inside lol. I’m down here by Broken Bow Oklahoma couple hours away. It’s just starting to hit us here.