Should the choke close completely?

Discussion in 'Carter' started by mercer, Jun 3, 2008.

  1. mercer

    mercer Well-Known Member

    Hi, when the car is cold should the choke close completely or should there be about a 1/8th inch gap to let a little air in?

    Assuming it's supposed to stay open 1/8th inch, what makes this happen? I have an electric choke and it closes the choke completely when cold - and as a result the car won't run at all.

    Regardless of temperature, when I close my choke completely, the engine dies.

    Is this proper function?

    Thanks!

    mercer
     
  2. 12lives

    12lives Control the controllable, let the rest go

    What car and carb is this on? In general, the choke will close until the engine fires and the vacuum (choke pull off) will open the blade that slight amount (1/8th inch) to keep it runnning.

    -Bill
     
  3. DaWildcat

    DaWildcat Platinum Level Contributor

  4. mercer

    mercer Well-Known Member

    That's correct, carter AFB four barrel, model 4055s. However, it's an electric choke.

    The spring pushes the choke completely closed, even with vacuum pulling against it - it's quite tight.

    If I adjust the spring looser, I have to make it a LOT looser - about as loose as it will go, at which point, yes, the vacuum is sufficient to pull the vent open - but the choke opens completely in about 35 seconds, WAY to fast for the engine - so it runs for 30 seconds or so and then dies. At which point I repeat, and repeat, and eventually, the car is warmed up enough that it runs.

    This #$@$ electric choke is a disaster. Has everyone had this much trouble with them?

    My original choke was completely damaged, not only the choke, but the hose, and the vacuum pull off from the carb had been filled in with epoxy - not even drillable, it's completely closed off.

    A switch to an electric choke seemed like the obvious answer, but this setup is crap.

    Currently, I have put a stopper that keeps the choke open a little bit, and then set the spring stronger, so it opens about the right amount to start, and takes longer to loosen up. This gets the car to start, but in general, doesn't work well.

    Short of replacing my carb (which is great other than this choke fiasco) how might I go about fixing this?

    Thanks!

    mercer
     
  5. Jim Cannon

    Jim Cannon Loves that Dynaflow hum!

    I like to make it just touch the carb horn when cold, not too tight.

    Mercer-
    You say that the vacuum pull off was full of epoxy. Did you clean that out? Because if you did not, then you are not getting the required vacuum pull off on the choke and you are doomed to get what you report.

    If you can not get engine vacuum to pull the choke open, you need to replace the carb.

    Electric choke is not a fix-all. If the carb is messed up, electric choke will not fix it. Engine vacuum really pulls the choke open. Electric choke warms the spring to not pull the choke shut so hard. If engine vacuum opens choke too far, engine begins to sputter and loses vacuum, choke moves partly closed again and keeps engine running by choking it a bit. A clever self-correcting system.

    Try drilling the vacuum port out to feed the choke housing. If that doesn't work, buy another carb.
     
  6. 12lives

    12lives Control the controllable, let the rest go

    "If I adjust the spring looser, I have to make it a LOT looser - about as loose as it will go, at which point, yes, the vacuum is sufficient to pull the vent open - but the choke opens completely in about 35 seconds, WAY to fast for the engine - so it runs for 30 seconds or so and then dies. At which point I repeat, and repeat, and eventually, the car is warmed up enough that it runs."

    I appears that it can work but the choke opens too quick. You might try a different choke. I believe the NAPA electric unit has a temp sensor vice a timing control and will not let up until the engine is warm (ie - longer than 30 sec). You would then adjust the choke so it will open up at start and the eingine should stay running as the choke will be "on" until it can run without it. See: http://www.v8buick.com/showthread.php?t=114581&highlight=electric+choke

    Note post #9 in this thread: http://www.v8buick.com/showthread.php?t=146223&highlight=electric+choke

    -Bill
     
    Last edited: Jun 6, 2008
  7. Buford

    Buford Old guy member

    The electric choke will work fine if you get the vacuum pull off mechanism working. It is common for the hot air tube going through the exhaust manifold to develop a hole (rust), then the light vacuum sucks exhaust and jams the pull off assembly. Setting the the choke blade lightly closed when cold seems to work great for me. Sometimes you have to tinker-tune a little for each engine, but a reliable setup when dialed in. I have used it many times. Good luck, rank
     

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