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Carb adjustments help needed - Holley 6520, 2.2 '84 K

Discussion in 'EEK! - Every Extended-K Car' started by Dodgem's Dad, Nov 2, 2017.

  1. Dodgem's Dad

    Dodgem's Dad Member

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    Good evening all,

    Last time I got such excellent help that I had to come back for more. I rebuilt the carb, assembled same in the car, snugged it down and checked all the vacuum connections. It ran so much better, but it was raining and cold so I didn't take it much further.

    Today I tried to follow the instructions in the shop manual to adjust choke and idle speed. When I set things up as requested it ran so rough it would not stay running. Manual had me remove the PCV, plug a hose, disconnect this and jump that, but it wouldn't cooperate. When put all back together it ran nicely enough but at a very fast idle, 1600+RPM. Nothing would let the idle "kick down" to a lower calmer idle.

    Does anyone have any manageable methods for adjusting the fast and curb idle on this? Turning the screw on the idle speed control solenoid had no effect and neither did the screw on the fast idle speed cam. Also need to adjust the mixture once all the rest is OK. Any advice is appreciated, but know that I can't reciprocate until someone has a question about a simpler '47 DeSoto with Fluid Drive and Tip-Toe shift!

    Thank you,
    Justin
     
  2. pt006

    pt006 Active Member

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    The solenoid is different for different years. It increases the idle speed a little when the AC is turned on. Check for a vacuum leak. Check that the fast idle cam screw is not touching the fast idle fast cam when the choke plate is fully open. Some solenoids controlled the curb idle by adjusting the idle speed with a 1/8" allen wrench. Others may know more.
     
  3. ImperialCrown

    Level III Supporter

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    Not exactly your carb, but check the 'Throttle Stop Speed Screw' adjustment (if yours has one). I have found these cranked down by someone thinking that it was an idle speed adjustment screw. It should be backed off until the correct idle speed solenoid screw takes over as the throttle stop.
    Choke mechanisms at the front of the carb could be troublesome. As mentioned, the choke plate must be fully opened and the fast idle screw completely off of the cam steps.
    The plunger at the tip of Idle Stop Solenoid needs to make contact with the throttle lever when the carb is at warm curb idle. If the ground contact can't reach the lever, then something may be mechanically binding or holding the throttle open?


    [​IMG]
     
  4. 85lebaront2

    Level 2 Supporter

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    I would look at a few things, first, does your car still have the rubber isolator mounting? If so they were replaced in a TSB years ago due to cracking in the rubber section. Second, are both throttle plates fully closed with the idle stop backed all the way out and the choke held open? I have run into Holley carbs before that the secondary would stay partially open. Third. power brake booster leaking? Disconnect and temporarily cap the fitting. Fourth, EGR opening or stuck open, disconnect the vacuum line to the EGR and with the engine running squirt a little water on the pipe feeding the EGR valve or on it's body if the rpm does not come down with no vacuum signal. If the water flashes to steam instantly, the EGR is open.

    I wish I could come there and help, I operated a carburetor and ignition shop then worked at a local Dodge dealership in my past.
     
  5. Dodgem's Dad

    Dodgem's Dad Member

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    Thank you for your input. After some experimenting I made a tool to help me access the mixture screw. I gave up trying to set idles as prescribed by the manuals. If I disconnected this and jumped that and plugged the other as the manual directs then the car would not run and would only barely start. With the car running and warm I adjusted the mixture, 23275520_1969721963054511_1457573077062579385_o.jpg throttle stop screw, the solenoid stop, and the fast idle screw. Everything is so much better but I will recheck all the adjustments tomorrow now that I have given it some exercise. It is very different from my aging everyday driver, a '90 Buick Reatta, but it is so sweet to drive.
     
    ImperialCrown likes this.
  6. 85lebaront2

    Level 2 Supporter

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    That is a beautiful car, Chrysler or Dodge? From the angle it's hard to tell.
     
  7. Dodgem's Dad

    Dodgem's Dad Member

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    Don't let the "luxury" wheelcovers fool you. They were a $45 option on this Plymouth.
     
  8. Dodgem's Dad

    Dodgem's Dad Member

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    Can I get away with asking the same question all over again? I had the Reliant out last week to have the car Krown sprayed for winter. I have a fear of rust ever since I had a 1954 Plymouth in 1974. When I turned it off it dieseled and then would not start again until a few minutes later and then only when I kept the pedal floored while cranking. Not exactly the scenario I wanted when handing it over to a tech when I need him to respect my car.

    I finally got back to it today. It starts fine but warms up sluggishly and slowly. The fast idle and curb idle are on spec, but it never seems to find the correct idle without help. Once warm it is smooth but it will not kick down to idle; it remains on a fast idle. If I force it by pushing the step below the fast idle adjustment screw it will drop to curb idle but once I hit the gas it will jump back onto the step and race at the fast idle.

    If I turn it off when it is on a curb idle it doesn't diesel. Turning it off on a fast idle gives it the death-rattling post ignition.

    How do I get the fast idle to obey?

    I did readjust the mixture. The last time was an improvement but in the middle of the operation the tool I made slipped and dropped on to the manifold and melted a bit before I could find it. This time I tied a wire to it so I could turn it without losing it. Its just a piece of an 11/32nds Allen wrench inserted and fixed to a radio knob.
     
  9. ImperialCrown

    Level III Supporter

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    Choke problem? The black, round element at the front of the carb with the single wire to it heats a thermo-spring and gradually brings the choke butterfly plate open.
    Wells-E683-Carburetor-Choke-Thermostat-1980-87-Dodge.jpg
    After the car starts and oil pressure comes up, you should have battery voltage at the choke heater wire.
    The plastic choke cam with the steps and its return spring had problems with sticking.
    With the engine cold, the thermo-spring should snap the choke butterfly shut. It should open fully without binding by finger pressure pushing it open and snap shut without binding either. Any 'creaky' feel while opening or closing would indicate binding. A good penetrant, maybe with foaming colloidal graphite like Mopar rust penetrant is a good lube for chokes. Avoid any oily, WD-40 type lubes.
    64912d1501337324-look-what-i-bought-100_1731.jpg
    With the air cleaner hose plugged, start the car. The choke plate should open slightly after starting and the engine should run at a high idle and fairly smoothly. If it is rough and sputtering like it is loading up from being over-rich, adjustments may have to be made. If you push the plate open a little more with your finger to let in more air and it smooths out, that would confirm that it is too rich.
    After several minutes and the engine is reaching a warm temperature, you should be able to blip the throttle and the fast idle screw should fall off the last cam step.
    0900c15280251a59.gif
    Once warmed, the choke needs to stay fully open and the fast idle screw needs to stay off the fast idle steps.
    If the fast idle cam get back underneath the fast idle screw again, then the thermo-spring element may be defective and need replacement. It grounds at the carb body at a metal tab at the lowest screw. It is a blind screw whose head shears off where the correct assembly torque is reached. The choke kit included 2 new rivets and a new shear screw.
     
  10. Dodgem's Dad

    Dodgem's Dad Member

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    The black, round element at the front of the carb with the single wire to it heats a thermo-spring and gradually brings the choke butterfly plate open.
    Wells-E683-Carburetor-Choke-Thermostat-1980-87-Dodge.jpg
    After the car starts and oil pressure comes up, you should have battery voltage at the choke heater wire.

    I'll try checking this tomorrow. I have fiddled with the choke spring twice, drilling out the rivets and slotting the screw to open it up, but everything is clean and assembled as it should be. Now that I know when I should have current to it I can check it. Thank you very much.
    Justin
     
  11. Dodgem's Dad

    Dodgem's Dad Member

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    I have current to the choke heater and the two metal layers in the choke assembly sandwich are grounded. That did nothing so I hooked up a direct lead from the battery to the heater so I could browse without the engine running. After about five minutes nothing changed. I could force the fast idle screw off of the stepped cam but if I nudged the linkage it was eager to get back on the cam.

    Does this point to a dead heater? Everything moves freely and I doubt the spring could be too snug in the housing without breaking the plastic housing.

    Once again I sincerely thank you,
    J,
     
  12. ImperialCrown

    Level III Supporter

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    Good test. Yes, once the choke fully opens and the heater is still active, it should never walk backwards onto the fast idle cam step. The choke heater element sounds like it is failing.
    Although the grounding sounds good as well, I always clean the choke ground ring and bend the bottom tab slightly toward the 'horseshoe' retainer for better contact.
     

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