edelbrock 1406 carb. A/F mixture screw.

the p***enger sde A/F mixture screw I can turn all the way in and it doesn't do anything, no change. the drivers side I can adjust, anyone ever have this problem? I have a fuel regulator on and its at 5 1/2 lbs.

 

When you say A/F mixture-do you mean the idle mixture screw on the front of the carb? (p***enger side)

 

you have a vacuum leak

 

Angle, yes. 57, I sprayed the carb. gasket, and the intake with either, and no leak.

 

The way I have adjusted the lean idle before is
-Bring the idle down low
-turn one screw in until the engine stumbles-back it out about a turn
-do the same for the other side-set the idleback up where you want it
-Done

just a thought-maybe the float is set too high and flooding the idle circuit?

 

I;ve been trying all kinds of things, the screw doesn't change or stumble, nothing. the drivers side works the way it should.

 

Had the same problem on my Cub Cadet mower. Tiny piece of trash. Hit it with some air and back to mowing.

jack vines

 

contact edelbrock's customer service/tech line and see if they can help. They helped me with a tuning problem in the past. Good luck!

 

I think it's funny I am here looking for help for the same exact thing. I also noted that while idling I can see gas dripping in the p***enger side throttle opening. I'm getting ready to go out and use some low air pressure to blow out any trash that maybe in the circuit. I had hit the throttle pedal hard about a week ago and from that point on it started running rough at idle. I replaced all fuel lines and filters along with new mechanical pump because i saw how the fuel in the filter was erratic. Figured pump either had trash or had started going out.

 

Very possibly the float(s) might be adjusted too high or some debris is trapped in one or both float valves...might need to dis***emble carb and clean it up. You might try blowing some compressed air into the low speed circuit (idle mixture screws) after removing the screws with the springs. Then for initial adjustment start with the screws out two turns from lightly bottomed in their seats.
These carbs are not complicated and most often if they don't work properly there is a dirt or debris issue. Good luck, *******

 

Thats correct. Your float adjustment is off. You need to take the top off the carb and lay it upside down. Then using a 15/16 drill bit, lift the float and slide it between the top cover and the float. adjust until snug, then let the floats hang while the top is still inverted, set that level as well.7/16.. High and low float adjustment is needed....

If you find debri in the float bowl area, a rebuild is required. Same as debri in the needle and seat....

I am sure after the engine is warm, and you shut it off, you get white smoke out the top of carb as well...

 

I had an Edelbrock with the exact same problem. I found an aluminum sliver in the pri venturi booster, a left over from the manufacturing process.

 

These carbs are very simple to clean. Start with a clean work area, and lay all the parts out in the order you take them off. Spray some rattle can carb cleaner in the holes, and blow out with compressed air. Use WD40 on both sides of all gaskets before re***embly, then they can be used again. I use a stainless steel tooth brush to clean parts. Dont over tighten the screws, just snug.

 

POWbucket, mine too at idle the gas is drizzling down the p***enger side venture, kind of weirdly drizzle. then the idle kicks up and down.

 

Time and time again I say even if the carb is brand new open it, clean it, set the floats. You'll save so much trouble.

 

I don't have my Edel carb books here at home, but I think you got that drill size wrong when you wrote 15/16" there Mustang1647, typo?
But I agree, you're time and trouble saved if you remove top, clean bowls and reset floats.

 

I had one that did the same, take the needles out and swap them side to side. It will tell you if its the carb or the needle. Turned out one of my needles was jacked up. When held side by side it was obvious its tip was blunted and didnt seal. 2 new screws and i was back in business

 

Nope, No typo.... here is a link, go to page 9 on the adobe or 9 on the leaf let and look at the illustration for clarity...Under float adj....

http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf

 

Take the screw out and spray some carb cleaner in the hole while it's running - does that change the running of the engine? Is there any vacuum there with the screw out and the engine running?

 

Mustang 6147 is telling how to adjust the float drop...reread his post!

 

both screws are the same. so I switched them, still the right side one I can seat it and the motor runs the same, no drop in idle. I did spray carb cleaner in the screw hole, and blew it out with air NO change. but takes the throttle well great response. just can't dial it in.

 

I think you and Mustang 6147 need to reread his post and the Edel booklet. The float level is adjusted with the cover inverted with a 7/16"bit between cover gasket and float. Float drop is adjusted with the cover right side up and a 15/16" drill bit inserted into the same spot.

 

Mine did the same thing. I didnt have a fuel regulator so I put one on and set it at 4 1/2 lbs and it ran great.

 

chainsaw, u mean you could turn the p***enger side mixture screw in all the way and it did nothing. ran the same no changes in idle.

 

dirty old man, your right I read the edelbrock sheet. JAN

 

Ok so this morning I took the Carb off and tore it down. I did a complete rebuild and was very very careful with all the adjustments. I checked and rechecked the float several times till I had it dead on. I then bend and adjusted the accelerator pump rod several times till it was dead on. Again this thing must of been dropped from a roof..LOL. Anyway runs like a scalded dog. Of course buying the complete rebuild kit is a lot cheaper than buying a new one. I want to Thank all who posted on the thread and everyone on HAMB for a wonderful tech packed website. I was able to get to the 4th of July Parade in Castalia NC to ride some Vietnam Veterans in the car. It's always a honor to hang with the Veterans.

 

Yes, no change when turned all the way in. It also had a bad surge, seamed to be firing on half the cyls. I have a performer manifold, each half the carb feeds certain cyls., cant remember which ones now. It might have been a fluke but the regulator fixed the problem on mine.

 

so I just got in from taking the top of the carb off. the inverted hang of the floats were 1/2" I bumped them down to 7/16". the hang of them was 1 1/4" I set them to 1" to 15/16" installed the top and I can turn the p***enger screw in to seat it and NO difference, it doesn't die or change the idle. and I did it again, I sprayed carb. gasket, and intake gasket while idleing NOleaks. the only thing va***e I don't have connected is the trans. module., but the intake is pluged. WHAT'S UP!

 

either way is right.... They illustrate it because most people don't have a third arm to hold it while the other 2 are measuring. LoL

I did mine like I said and it was correct.... The guy before me did it and my symptoms where exactly what this guys issue is.... No biggy, mine works


How did the inside of the float bowl look. My guess is, you got **** blocking a p***age.

did you check the needle and seat for debri?

 

Every Edelbrock I've had has pushed fuel through the needle and seat above 4.5 P.S.I.