have one on my car and I know it needs to be adjusted real bad.If I start the car in the garage it gets so fumed out in there that you may die if you stay in there.Plus the smell gets in your clothes real bad also.I need to know how to go about adjusting the 2 front idle circuits.Just a step by step.I have the manuel and it dosent help much. .I know we must have some carb gurus on this board.<!-- / message --><!-- attachments -->
I suggest you read the owners manual ... All of your questions will be addressed in it ... IF ... you do not have one ... Go here for the on line manual ... http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf
If it's a hi mileage unit it's junk. Edelbrock doesn't care about making a better carb ( revising its rebuildability) as long as they keep selling.
What are you talking about? They are probably the most re-buildable aftermarket carb out there. The AFB design has been around forever, very few moving parts or gaskets.
Most carburetor problems are not carburetor problems. Make sure you don't have a vacuum leak, and your ignition system is in top shape. It's pretty rare to have a carb as rich as you describe without other factors coming into play. BTW, it's never gonna run clean enough to run it in the garage for more than a few seconds. Cold start+10 seconds will fill the place with fumes. It's not an F.I. 4 cylinder with a catalyst Once you're sure it's the carburetor, edelbrock sells calibration kits around $70. Their tuning instructions are long and good. Also be sure it's not full of gunk. Lots of guys skimp on fuel filters and our old gas tanks fill em with crap. Doesn't take much. good luck
Everything is fresh and only has 100 miles on it.No leaks of any kind.Even when fully warm its stiil has same problem.I read through the manuel.I dont see anything in it to adjust the 2 front screws.Can anyone help a guy out. Thanks
Try turning the screws in and out till you get the highest vacumn reading. Probably will need to adjust idle again and chect timing.
Ballpark that has allways worked for me, turn the screws all the way in, then turn them out 2.5 turns. That has usually set a baseline to work from. Check your timing and adjust your idle, check for vacuum leaks as well. Good luck
MAKE sure fuel pressure is not over 4.5 psi!! First thing that you need to check!! (Got that from Edelbrock tech Line) I also have a CD Rom sitting in the glove box on how to tune Edelbrock carbs if interested...
Really? 4.5psi? I've been thinking of adding a regulator to my car, but it's supposed to be that low than I definitely will!
also check the float levels, and tell us about the choke setup on it. Cold start problems are usually caused by the choke. Once it warms up, then you can mess with the idle mixture (those two screws up front), and then if you have driveability problems you would get into the jets/metering rods/air bleeds.
This is there out off the box setting(2.5 turns out). I'd start there. Usually from there I found about 1/8th turn in from there is good for anything 300 c.i. +. But keep in mind this only idle mixture. Anything off idle will not be affected by this adjustment. so it might need jetting from there. I don't know what the high milage comment was about. They've always been long lasting units for me. I've let a few sit on the shelf in the garage for years after being run for years. And when I go to use them again, they do fine. I prefer holley in a performance application. But for stock daily drivers they are my preference. Hope this helps.
I had the same problem with a 1406 that had me baffled for a while. Did everything that was suggested, took the carb apart and cleaned it out set up the float levels etc checked for vacuum leaks and got the timing spot on. Ran like a pig and drank fuel. Do you have an erratic idle? If so take the carb off again and check to make sure that butterflys on the primary have not come loose. If they have you will have no chance of getting it to run right as you are setting the idle mixture with a huge vacuum leak. Mine were so loose that I was lucky that I did not lose a screw down the bore! Hardest part is getting the butterflies central in the bore so they do not bind and are not too 'open' at idle. Think there must be a feeler gauge setting somehwere but I could not find one so ended up doing it by trial and error. On the plus side all of the pain meant that I now know how to take apart and tune an edelbrock carb and I have a really nicely tuned motor from chasing this particlular problem around the car. Hope this helps, P.
Another thing...many aftermarket aircleaners are junk. If no one has meddled with the carb, try just rmoving the cleaner while it is running and see if behavior suddenly changes.
You don't say what engine your runnin so heres my .02. Most of the time the Edelbrocks come with the largest metering springs installed. Buy a step up kit for it and put smaller springs in the carb.Once done, reset the idle mix and idle speed.Turning the screws out richens the carb and in leans the carb.Start by getting the motor warm and turn 1 screw in at a time until the motor starts to stumble, back it out to highest idle and then back in again til you notice a r.p.m. change. You can also set the accelerator pump to a differant postion.Try the lowest point 1st.On mine I had to do all of it I mentioned to get it right. Good luck and they really are a good carb to use and an easy one to work with
yeah, everybody NEEDS a Q jet.Hell I've got probly 20 in a junk barrel.Don't get me wrong, they ARE good carbs until they start f-ing up and then they ARE junk.Nothin wrong at all with Edelbrock carbs if ya know what you're doing when you set them up and they are easy to repair as they only have 1 gasket and that's at the top above the gas line so you can adjust the float.I think you're off base a little there
Choke is electric and works like a timex.I dont really have any drivability issue.Its just the fumes will kill ya.I am gonna try to adjust those 2 circuits.
Screw one of the idle "screws" in 1/2 turn at a time until the idle just starts to drop or get rough. Back it out to the spot that levels it out and about another 1/2 turn out. Do the other one and then set your idle screw. It'll be real close to right. BTW, most carbs are rebuildable until the throttle shafts wear out. Unless you're following some one that has been into them and modified them with "speed secrets". Larry T
Idle is an issue.It seems that I have to keep bumping it up.Its either fine or its too low.I will check that also. Thanks
Larry T set me straight on my throttle shaft bushings ins and outs and how not to put my foot in my mouth.
I have an edelbrock 1406 with the electric choke and it starts great when its cold but once you get it up to operating temps and shut it off you have to hold it to the rugs to start it after it sits a couple minutes but if you start it up right away it will start fine. I have checked the choke out and it is working properly. Any ideas? Thanks
If the carb and manifold are new to the engine, check for vacuum leaks. Are all the vacuum ports on the carb connected or blocked off? Put a vacuum gauge on the engine and start it up. If the engine is stock, the vacuum should be steady somewhere around 17 inches ( the number isn't as important as the fact that the needle is steady). If the vacuum is low after you have adjusted the idle jets to max vacuum, you need to check all the hoses for a leak. Was the engine running correctly before you swapped the carb? Go through the installation instructions step by step, if you are not too familiar with setting up a carb it is easy to miss something. I have never run an Edelbrock, but I have run many Carter 4 barrel carbs. They are as good as anything else out there. They were good enough to be original equipment on most 50's and 60's Corvettes and some awesome Dodges. I only preferred the Holley because I got used to all the little tricks for setting Holleys up and it was easier to change main jets on the Holleys at the strip to allow for the altitude or the weather. I also like the Q-Jet for street use, but they are a pain in the butt to overhaul. Bob
That is the same problem I experianced. Set the idle, rev the engine, idle now too low. Set the idle, rev the engine, idle now too high. Repeat.... Disconnect the throttle cable and, with the engine running at a high idle and the idle screw wound all the way in (so it is not touching the throttle stop) try and pull the throttle shut. If you can, this is exactly the same symptom mine displayed. Take the carb off and flip it over and check the screws holding the butterfly to the throttle shaft. If they are loose then the butterfly will have moved in its relation to the throttle body and 'presto chango' you get the symptoms you describe. Let us know how you get on. P.
I got this carb on a 283, and it has the same problem. I just got the car on the road (after almost two months of the state of NJ jerking me around). After reading this thread, I checked the fuel pressure and I found the needle swinging between 10 and 15. Holy shit, I didn't ever think that a mechanical pump would be that high of a pressure, I wonder what the application could have been? Anyhow, I put on an old pump with 6 lbs pressure and now the thing runs really nice. still gets a small puff of black smoke when snapping the throttle, but not near as bad as it was and the flooding after sitting hot statring problem is gone. Smells a lot better, too. Frank
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