c4 troubles

Discussion in 'Transmissions' started by AtroXR7, Aug 8, 2007.

  1. AtroXR7

    AtroXR7 Member

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    I've come to think the modulator line is not connected, but the issues seem that they might not be the same.

    Car came with a hurst pro-matic 2 shifter. At first I thought maybe the linkage wasnt right because I cant get neutral. But ive check each position on the cable with it not connected to the shifter, and they all line up perfectly.

    So park is fine, reverse is fine. Neutral puts me in drive most of the time, but sometimes will flare into neutral and then back to drive. Drive, when i first start the car, goes into first, and hangs, i often have to manually put it in 2nd and then back to drive. After the initial encounter with 1st gear, i rarely can get it back, it stays in 2nd at a stop. Manually shifting to 1st does nothing. 2nd gear is the pride and joy, the car wants to stay there most of the time. Getting into 3rd can happens sometimes if i take it all the way up to 70 or 80, often i have to play with the shifter... in and out of neutral and 2nd and back to drive and it will eventually click up the 3rd. I havent tested if manually putting it in 2nd will take me back down from 3rd... when i get 3rd i tend to try to keep it, gas isnt cheap.

    Like I said, i found a vacuum line open, it looked kinda like a HVAC type line, but im guessing it may be for the tranny. Its pretty long, looks as if it could reach to the front of the carb or beyond maybe... engine was too hot last time i had the hood off so i didnt spend much time playing with it.


    I also have a bog down from a stop often, feels like im not getting vacuum advance maybe? where should the advance line be comming from, the lines just dont look to be in the right spots to me and I dont have a diagram to help at the moment.
     
  2. don graham

    don graham MCG State Rep

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    if the modullator line is not connected that should be pretty easy to spot. line comes from the middle of the modulator on the passenger side of the tranny, up near the firewall and to a vaccuum port near the rear of the carb, down toward the base plate. at least that's the way mine does. as far as the shifter goes i would get a copy of the install instructions and see how hurst says to adjust it. i know my b&m can be a little tricky at times. btw i went to checkers and found a b&m shifter there and asked if i could make a copy of the directions. they said sure. :)
     
  3. AtroXR7

    AtroXR7 Member

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    good progress so far, previous owner had the modulator line connected to the fuel bowl vent. no good could have come from that. So now thats fixed and the only issues I seem to be having are shifter placement. park works, reverse works, neutral is the best spot for drive now. drive through 1st are pretty much all 2nd gear most times i try them. but at least now i can let the tranny do the work and its shifting great. Car is so much more fun to drive when you're not taking off from 2nd gear all the time.
     
  4. PaulS

    PaulS Member extrordiare

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    It sounds to me like the shifter is the wrong length.
    It is not lining up as it is used. The way to adjust the linkage is to put the shifter into Drive with tension on it toward 2nd gear position but held by the detent in Drive.
    Then connect the linkage to the transmission lever when it is in Drive. Adjust the linkage so that the lever doesn't move as it is connected.
    Paul
     
  5. AtroXR7

    AtroXR7 Member

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    now that ive had some more time getting used to the car, I think i have it figured out. i dont know that its aligned wrong, but simply the shifter doesnt travel far enough to reach all the gears. park seams like it doesnt fully engage, but it does work so its not a concern really. Reverse clicks in just fine, neutral work if bringing it down from reverse, but not if you take it up from drive... unless i ratchet up really hard as ive had to do a few times when i stalled in an intersection... (accelerator pump doesnt always work right). drive is the same, down from N is good, up from 2 isnt. 2nd always works, and i simply cant get it to click into 1st.

    so it seems to me that since it can reach neutral or drive from the middle, and cant reach 1st, that maybe the motion of the cable just isnt adaquate from the shifter side... i'll try to adjust a few things but i have my doubts. I think i may be able to modify the distance the shifter will pull when ratcheting to get it all the way into the next gear, after all, im probly missing by like a mm.

    Im not doing it today tho, i just razored all the old purple tint off the windows and ive had enough for now
     

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