New guy with a quadrajet issue. I just rebuilt a qjet with a kit from Cliff Ruggles (hopefully correctly) and just installed it. At idle and under normal driving conditions but when I try to go full throttle I lose all power and there is very little acceleration. Is this a vacuum issue or something else? I have roughly 16-18 on my vacuum gauge at idle and normal driving. All vacuum tubes come off of my manifold. I have nipple caps on all the nipple on the carb. Then again this may be a totally different issue than a vacuum problem. It is a 77 qjet on an offy 360 bolted onto a 68 Toro 455, crammed into a 67 Cutlass.

Thanks,
Rik

 

Does your accelerator pump work?

Have you adjusted your secondary air valve?

Welcome to ClassicOlds.

- Eric

 

 

So do I have to take the entire top air horn off to adjust that? Yes, I know very little about carbs in general. But, trying to learn. Thanks

 

No, you loosen the Allen set screw and rotate the spring tensioning screw a specified amount, depending on the engine configuration.

This is a standard adjustment, and should be laid out in the directions that came with the rebuild kit (it is in the generic auto parts store kits), and, since you used Cliff's kit to rebuild your carb., it would be fair to call and talk to him about it if you are having trouble.

My next question is - How did it work before you rebuilt it?
If the air valve setting was about right before, it shouldn't be any different now.
If you didn't place the check valve BB where it belongs, on the other hand, the accelerator pump won't pump.

- Eric

 

It's a totally new carb for my set up. It had a might demon on it prior. I bought the qjet and rebuilt it. It was my first go at it. I did the whole tapping an old bb with a punch and inserted a new bb. I am assuming my spring on the secondary may be too tight? Thanks for your help. I have a email into Cliff, but I'm impatient and wanted some possible solutions ASAP, can't help it. Thanks brother.

 

I bought it and rebuilt it. It had a mighty Demon on it before. I did the old bb tapping trick prior to replacing with a new bb (not saying I didn't screw that up). I have pretty smooth acceleration up until about 3/4 throttle. When I "floor" it the RPM's initially jump then settle back at which point I have almost zero power and acceleration. I am assuming (based on what I just read in another article) I should reduce the tension? I appreciate your help Eric.

 

Sounds like you need more spring wrap because your secondary air valves are opening too soon.

You realize the choke unloader vacuum canister also serves to control the secondary [2'] opening rate, right? Is that in place with link to RH end of 2' air valve shaft, adjusted correctly?

 

I'm so new to qjets (and carbs as a whole) I couldn't tell you if anything is adjusted correctly. All I can say is that everything is connected to what is was prior to rebuild. I have read and reread the instruction and they are useless to me. Yep, I'm that guy. Thanks for the help.

 

Easy to try the spring wrap, the manual calls for 3/4 turn w a 455.

The service manual has a real nice section on the qjet and set up if you don't have one that can really help.

 

Pictures, then. We need good photos of all sides of the carb.

And also, check to be sure you have two solid streams of fuel from the nozzles when you look down the primary barrels and open the throttle.

And, also, also, read the section on QuadraJets in the Chassis Service Manual - it will tell you how the carburetor works, which will help you to understand it.

- Eric

 

Ok call me an idiot (I'm used to it). Yeah this rookie never put on the secondary cam for the secondary metering rods. So, I have pulled the top off put the cam in place, adjusted the tension and now we're good to go. Thanks all for you help.

 

Well... That'll sure do it.

Glad you got it fixed!

- Eric