Tranny problems. Help Please

Discussion in 'Technical' started by Bob Wiken, Mar 19, 2008.

  1. Bob Wiken

    Bob Wiken Chronologically Gifted

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    I just got a c4 from a junk yard installed in my '73. New filter. Fluid is full. The car goes into reverse and almost immediately kicks back into neutral. wait a few seconds and goes back to reverse. Shift into drive, goes forward and immediately goes to neutral. It took about a minute and a half to transverse my driveway that is about 75 feet long. When it goes into gear, it seems to go in smartly. It just doesn't want to stay there. Any ideas??
     
    Bob Wiken, Mar 19, 2008
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  2. Chinguschild

    Chinguschild The Bass Player

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    slipping like crazy? Shot valve body? I'm at a loss.
     
    Chinguschild, Mar 19, 2008
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  3. Eddie Maverick

    Eddie Maverick General Garageman

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    I think we need Paul S to jump in on this one.
     
    Eddie Maverick, Mar 19, 2008
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  4. eddie1975

    eddie1975 Windsor Specialist

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    sounds like a V/B issue
     
    eddie1975, Mar 19, 2008
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  5. PaulS

    PaulS Member extrordiare

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    Oh sure, you guys answer all the easy ones.....
    If it goes into gear and then pops into neutral it is probably an issue with the line pressure limit valve. It is the one that the filter holds in the valve body.
    What it means is that either the spring and valve are faulty, the pressure regulator valve is stuck or someone boosted the line pressure over the 270 PSI limit.
    You can probably fix it by removing the valve body (no removal of transmission needed) and carefully remove each valve, clean and polish by spinning it with an electric drill and buffing the valves with 600 grit emery paper and kerosine. If you are good about the details you can take all the valves out at once and thoroughly clean the valve body with all the valves out but I would recommend that you do one valve at a time so no valves get put in wrong or springs and valves out of sequence.
    You can also modify the valve body while it is out for better shifts if you go to the information in my tech post on how to hot rod the C4 (found in the technical forum - the last pages are on the valve body mods)
    Let us know what you find - OK?
     
    PaulS, Mar 19, 2008
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  6. eddie1975

    eddie1975 Windsor Specialist

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    Paul you fart smeller(y) err smart feller:thumbs2:
     
    eddie1975, Mar 19, 2008
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  7. PaulS

    PaulS Member extrordiare

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    I don't know from smart but after 30 plus years building C4s I should be able to fix it over the net..... I am not that good!
     
    PaulS, Mar 19, 2008
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  8. Chinguschild

    Chinguschild The Bass Player

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    DUH! I'm not a mechanic. And I wont even dare touch my own trans yet
     
    Chinguschild, Mar 19, 2008
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  9. PaulS

    PaulS Member extrordiare

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    Just pay the round trip shipping and an extra $700 to $800 dollars and I will build you a 400 HP C4....
    My next project is building AOD's that can take 400 - 500 HP. I built my first one for my son's off road Bronco but it will be over a month before he gets it in and starts testing. Anyone close by want to be a guinea pig? (close to Seattle, so I can fix things when they break.)
     
    PaulS, Mar 19, 2008
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  10. 71gold

    71gold Frank Cooper Supporting Member

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    did you install the ..new filter...if so did you get the ...springy thing... back in or in correctly :huh:

    ...Frank...
     
    71gold, Mar 19, 2008
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  11. Bob Wiken

    Bob Wiken Chronologically Gifted

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    yup
    springy thing is in correctly
    :)
     
    Bob Wiken, Mar 19, 2008
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  12. 71gold

    71gold Frank Cooper Supporting Member

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    ...that's it for me...

    ...:Handshake...
     
    71gold, Mar 19, 2008
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