I sent two QJet’s to the Barker Gang Garage for them to pick one to be rebuilt. They chose the original QJet from my ’79 Corvette. I had asked them to convert the hot air choke to an electric choke assembly as I did a complete top-end rebuild two years ago and removed the hot air choke and emissions components. I have been using the other QJet and it developed a fuel leak at the fuel inlet housing. Once I installed the rebuilt original QJet, the choke didn’t operate. So, I have been trying to make adjustments to get the electric choke to function when starting the vehicle when cold. I noticed that all they did was replace the cap assembly on the choke. Not sure if that is really the way to convert a hot air choke assembly to an electric choke assembly. I still have not been able to get the choke to function. Once I got the car running yesterday, I took it for a spin and it felt like it was going to stall so I pull it in the garage and the top secondary blades are stuck wide open. After a few minutes of it sitting, I go to restart it and the choke engaged and I could never get the car restarted. It smelled like I flooded it. Not sure how to resolve this. It’s been a nightmare and disappointment thus far. I need someone who is knowledgeable to assist. Someone in the area willing to come over or willing to talk on the phone. I’m also willing to remove the QJet and send it somewhere or even buy any new carburetor that actually works.

 

They converted it to electric choke properly, all you do is replace the cap, there is a small vacumuum port inside the choke housing that needs to be plugged. Not plugging the vacuum port has nothing to do with your issues.

1. Get ahold of Lars' Qjet papers. Read them. Go relax somewhere and read them again.
2. Make sure all of the adjustments are properly adjusted. Pick up a copy of the Haynes Rochestor book and use it in conjunction with Lars' recommendations. In my opinion Haynes book is much better than the Cliff Ruggles book.

Details make the difference. I was struggling with my carb and tried one of Lars' tuning tricks in regards to the power piston. Sure enough, it wasnt seating at idle. I swapped out the spring to a softer one and now my car runs better than ever.

Regardless of whether or not you think your carb needs an adjustment you should check everything that can possible be checked and adjust as neccesary.

 

Honestly, I'm not interested in taking the carb apart. It has been rebuilt by a reputable company. I shouldn't have to take it apart especially since it was DYNO'd four or five times by them before it was shipped back to me. Yes, it was a different engine setup then mine but the QJet should work. I managed to get the car started today, choke still didn't work properly so I had to keep it running in order for it to warm up and stay running on it's own. Took it for a spin and when in drive with my foot on the brake, when I give it some gas it wants to stall. Like it's getting to much fuel. The exhaust smells rich. I'm not a QJet expert but I'd say that's a problem. I have the AIM and the Shop Manual.

 

How about calling the outfit that did the rebuild, they should warranty any work they did if it's not working as it's supposed to

 

I've sent several emails and waiting to hear back from them. It's just so frustrating. I'm ready to sell the whole car. I'm sure I would regret it later.

 

just read your thread, would like to make a comment if I can, first let me say that I am not trying to bust your stones. I understand where you are coming from about your Q-Jet problem, but jim2527 is giving you excellent advice, you should take his recommendations. Its sounds like you are looking for an easy fix, and yes it should work correctly from the builder, but that does not happen all of the time. IMO I don't think the AIM and maybe even the shop manual will explain to you what you are looking for. I am in the process of getting my BB together and you can bet I will try to learn as much as possible about the Q-Jet even if I have someone rebuild it, it sure won't hurt and look at much you will learn. Take jim2527's advice get the items he mentioned, and in a couple of hours or more you should be able to resolve your problem.

 

Sorry, Guy's. Just frustrated.

 

I don't doubt they're reputable, but perhaps they're not as knowledgeable on these carburetors as they are on others. I'm actually more concerned about the statement you made about the secondary blades being stuck wide open. Those are actually the air valves for the secondaries and are spring tensioned, with a specific adjustment. Plus, they're mechanically linked to the secondary metering rods. I belive these stuck open will cause a super rich condition. The choke not being adjusted properly will cause a very difficult cold start situation. Both problems at the same time, and I'm suprised it runs at all!

Like others have already said, the papers Lars has posted are fantastic. Frankly, I'd still be messing with my carb without them! You should be able to adjust the choke within about 15 minutes using his choke adjustment procedure. The secondary air flaps are a different matter, but easily adjusted. There's a set screw on the underside of the top of the carburetor on the choke side just behind the air flap shaft. That's where the adjustment is made. I'm not sure what yours should be, but I'd bet you can find it in your service manual. I think about 15 minutes worth of adjustments should have these things fixed. If the rest of the rebuild is good, you should be too.

 

Where can I find his paperwork? My Vette also stumbles on itself when applying the accelerator. Power Piston or Power Piston spring?

 

just ask him for it.. v8fastcars@msn.com

 

As mentioned if those are staying open on the secondaries all sorts of things will not work right. There is a small spring that holds it shut on the choke side, when you see the spring you will also see the set screw, but first look in the slot where the actuator rod slides, inside there is a small flat head screw, that is what you turn to tighten the spring once you have loosened the set screw. Turn the screw only so far that the secondaries just hold shut, then tighten the set screw. If those are open all the time its not good, and it is a simple adjustment. I bought a Qjet from a guy with a 79 to put on my 80, he sold it becaus ehe could not get it running right so he installed an Edelbrock. I found it had that same issue, I adjusted it and installed it and the car runs beutifully, Good Luck (and read Lars papers too).