My stock 77 350 has an edel 1903 on it and likes to stall/stumble when leaving an intersection. Thinking it is the accelerator pump. Edel reuses model numbers and said this carb hasn't been made for 14 yrs. Car has 60k on the clock and only 5k since 2006. Lady died, the son never drove it. It starts easy, idles well and got 13mpg on the first tank. Which is what mpg buick said it should get. Should I rebuild this one or is there something more modern that might get better gas mileage? Edel talks about their new annular boosters but not sure if that would a performance upgrade or possibly get better mpg's with it. For now, this is just a putt down the road gbaby hauler. (for now) Thanks in advance for the help!
You could rebuild it ,it does sound like the acc pump .Edelbrocks are A easy carb to rebuild ,and work on. That would be your cheapest ,but A good Q jet carb is hard to beat.
Since it seems it is working properly, except for stumbling, could I just replace the acc pump instead of a complete rebuild? Throwing 20 at it to possibly save 200 seems like a reasonable gamble but not sure if a wise one.
Personally, I would get a Quadrajet core and get it rebuilt by Quadrajet Power or Everyday Performance. Both guys are on this board. With a decent tune up , recheck timing I believe you can see better mpg then 13. Atleast put a vacuum gauge on it and see if it’s steady and 18 or better. There is a post on power timing and with a distributer recurve kit you should see a little better vacuum and mpg with more acceleration.
Ya you could just put A pump in it .The last rebuild kit I bought ,I got it from AutoZone for about $40.They are cheap, you get A new pump,gaskets in case you damage yours.
Yes it is. The car came fully documented. From original pink slip and window sticker to what looks like every service record included a stack of Calif. smog test certs. Is there a chance it came with the 1903? No receipt or maintenance record showing it had fueling issues.
No that’s not original. But if it’s a Quadrajet base carb , I’m sure Mark at Quadrajet Power could really work it over.
If you think it is the accelerator pump, why not just take a look? With the engine off, take the air cleaner off, move the choke blade out of the way if necessary, and rapidly move the throttle wide open. Look for 2 solid streams of fuel. If it is weak, you have found the problem. The E10 gas can wreak havoc with accelerator pumps not designed to work with it. The 1903 is a great carburetor. Keep it and send it out to one of the guys on the board if you don't want to work on it yourself. It probably needs to be gone through anyway. Mark and Ken have the updated pumps for modern gasoline.
Why the heck do people say things like recommending raising the Float when you can just look down into the primary and work the pump to see if it's working well. Just the slightest movement of the pump should move some fuel out the discharge tubes, and the pump is aways set up to be a good amount below the normal furl level so it takes a pretty messed up Float level setting to effect the pump! Note, check your pump shoot response with the motor off.
Lol. the pump is usually taking fuel from the bottom of the fuel bowl. Could be part of the problem but not likely. It is probably the pump is worn out. I would try it with the motor running all you have to do is give it about a 1/4 throttle and look to see if it is shooting, if it stumbles at all the pump shot is shot. Make sure you are totally warm all the way before testing. You can try to readjust the idle jets but probably will not help, just get it rebuilt and be done with it. I change the pump diaphragm in my Holley just because it sits all winter, may not need to but they are cheap and why be stuck at the light with the car stalled because the pump shot did not work.
Raising the level in many cases will clear up an off idle stumble, looking down the throat of a stationary car pumping the throttle has nothing in common with what's happening when the vehicle is shifting around leaving from a stop etc. im well aware of how a Qjet functions, one would think one would check pump shot,vac leaks etc before tearing into carb anyway. Good indication of a leaking acc pump is if it's wet there at the arm/shaft
The Q-Jet pushes down the Acc pump if not mistaken so wouldn't the fuel bowl be part of that filling? So if the fuel bowl is down some on the adjustment would that affect the pump shot since there is not enough fuel in the bowl? Sounds logical if this is how the system works. Or does the system suck fuel in from the bowl when the pump goes back up in travel. If the pump has to do that then it has to work going down and up pumping fuel. Guess that is why I use a Holley the pump in on the bottom of the fuel bowl.
