Carter carbuerator wont idle..dies when goes in gear ???

Discussion in 'Classic Mustang Specific Tech' started by 68 & 00 GT, Jun 22, 2009.

  1. so I got my 68 home after a 5 year paint job and the beginning of a law suit, but the carb is giving me isses. It's a 625 Carter / same as the Edelbrock. After I got the car started with some fresh gas the car will, run at high idle, and rev OK but it doesn't want to idle at low speed, and when I put the car in gear the engine dies.

    any suggestions ?
    I know these Edelbork carbs are pretty simple but I wondered if anyone can identify a specific issue with this before I pull it apart and go after it with some carb cleaner ? The carb wasn't left with any gas sitting in it so this kinda suprised me. I turned it upside down and it sounded like both floats were freed up and it sprays gas in the jet no problem.

    wondered if a fuel additive might clean it up ?
  2. Check for a vacuum leak somewhere. I was suffering a vacuum leak and my engine wouldn't idle below 1500. That would be the first place to start would be replacing the carb. gasket I think and make sure any vacuum ports on the carb. are properly plugged up.

    Also I know this is a dumb point but did you adjust the idle at all? The last thing I would do would be to adjust the idle fuel mixture. I think the carter's are the same as the edelbrocks IIRC so adjusting it should be simple and will yield much better idle and off idle results.
  3. what should the a/f adjusters be set to ? I think they are about 1-3/4 turn out.

    pretty sure all the un used vaccum ports are caped off.
  4. The way to set the Idle mixture is to close both of them off the entire way. It's easier if you have a vacuum gauge but if you don't it's simple too moreso you'll have to listen. What you do is then open one of the screws 1.5 turns out and turn the engine on. You then adjust it out until the RPM is maxed or if using a vacuum gauge you get the most vacuum. Don't keep going once highest RPM is reached or max vacuum is reached as you're just going to run rich.

    Next reset the idle of the car using the idle set screw. After you're done with that start on the other screw and adjust it 1.5 turns out and redo the above procedures. It's really easy to do and doesn't even need the vacuum gauge if you can listen to the RPM's or get a tach in front of you. Once this is done the manual says to close off the screws until you get a slight drop in RPM and this is the perfect setting which is a bit lean.

    I just left mine as is and didn't do the final adjustment cause I don't wanna run lean on idle.

    Hope that helps.
  5. doesn't matter which adjuster you do first ? Is one air and the other fuel ?

    sweet can you explain this "you then adjust it out until the RPM is maxed" meaning stop turning the adjuster out when the rpms wont go any higher ?
  6. I think they both adjust fuel one is for each side of the primaries. Yea just get it so RPM is maxed then reset idle and do the other side.