Muncie mania

Discussion in 'transmission and Drive train' started by Magicman7, Nov 4, 2018.

  1. Magicman7

    Magicman7 New Member

    I need help with my Muncie transmission. 1969 Corvette 350, Muncie M20 4 speed. All components are STOCK. The gear shift and linkage are STOCK, NOT Hurst. I had the trans rebuilt, put it back in, but I can't get it to shift through the gears. It will only go into 1st and I hit a brick wall when I try to shift into 2nd, 3rd, and 4th. I did align the shift levers in neutral before bolting them down. I have no idea where to go from here. ANY help would be greatly appreciated. Thanks.
     
  2. chromebumpers

    chromebumpers solid fixture here in the forum Staff Member

    Welcome Magicman7.
    When was this transmission rebuilt? Who did it? A shop or a friend? Can you take the transmission back to who ever did the rebuild?
     
  3. chromebumpers

    chromebumpers solid fixture here in the forum Staff Member

    I have several ideas and we have to begin somewhere, so I’m thinking it’s the shifter.
    The "proper" method to adjust the shifter is to back off the stop bolts (WAY OFF)
    Remove all the rods from the shift arms on the trans.
    With the shifter in neutral, install a 1/4" rod thru the body of the shifter, ALL the way thru the body (Both sides ).
    Make sure the shifter arms are in neutral, jiggle them back and forth so they are detented.
    Proceed to adjust the rods, one at a time so that they slip freely into the shifter arms.
    Get picky here. - this is the most important part.
    When you have the 1/2” and 3/4” rods all in place. - Reverse as well, remove the 1/4" pin.
    Shift the trans into 1st gear - Slowly tighten up the stop bolt untill it just barely touches the arm in the shifter body.
    Shift the trans into 2nd, do the same to the other stop bolt.
    Test drive,
    If it still won’t go in gear, grinds or pops out etc, Then you have a synchro issue..
    If you do end up taking the trans apart, replace the synchro "slider keys" Often overlooked, and new ones make one hell of a difference !

    Looking forward to your feedback before I lay out the next test.
     
    Last edited: Nov 4, 2018
  4. Magicman7

    Magicman7 New Member

    Thanks, I will do your suggestions in the morning. But, since this is the original stock shifter it doesn't have stop bolts. The rebuilder is not a shop but he was recommended by my Corvette club membership. He knows his stuff. He rebuilt it a couple months ago. He cut his hand severely on his day job so he is not available. Yes, I could take the trans to him but I hope to not have to remove it EVER again.
     
  5. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

  6. Magicman7

    Magicman7 New Member

    Rich, I went through all the instructions. I had to adjust the 3/4 rod slightly and the 1/2 rod quite a bit to get it to slip into place. But, the shifter will not move at all when I try to shift through the gears. I have the rear wheels off the floor and I was able to turn the tires by hand. I could shift the reverse lever manually (under the car) and the 1/2 lever manually. The 3/4 lever would not budge. It seems to be locked in two gears.
     
  7. Indycars

    Indycars Administrator Staff Member

    If it's locked in 2 gears, then the trans or rear wheels will not turn.

    Assuming the shifter does not lock-up when the rods are NOT connected, then the problem must be internal
    to the trans. I would start by pulling the side plate and inspect the trans from there. Can you manual move the
    syncro rings by hand and select each gear. Once the side plate is off, the problem might just be obvious. Pulling
    the side plate should not require removing the trans, thou you might have to remove the trans mount and
    lower the trans possibly.
     
  8. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    You have a Shift Lever upside down.
    Wrong non factory shift levers.
    The Plunger is broken that grabs engages each gate in the shifter.
    It's a Terrible POS The stock C3 Shifter.
    Only looks nice.
    They made direct fit Hurst Competition Shifters for a C3 Vette.
    Long gone discontinued.
    Near impossible to find NOS complete.
    Can use a Universal Hurst Competition Shifter.
    Must cut a hole in the floor or bigger.
    Console has to go.
    Install a Hurst Mega boot .
    Just like a Drag Race Car.
    It's 1 million times better a Race Hurst shifter vs that stock Chevy shifter.
    It was a POS In all Chevies.

    Hurst Factory installed in All Pontiacs 1964-1981 GTO, Trans Am, 2+2 Catalina with Muncie 4 & Later Borg Warner Super T10.
     
  9. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    Move the shift levers by hand with rods off.
    Each gear should engage.
    It's near impossible to break the internal shifter side cover interlocks.
    Have to bang gears with 2000 lbs pull and push force to do so.
     
  10. Magicman7

    Magicman7 New Member

    Thanks for your input guys. I think you are right about the problem being internal and I can easily pull the side plate but I need to have the rebuilder here because one gear looks like another to me. I rebuilt the 350 but transmissions are foreign to me. I hit the big "70" and I've owned this car since my early 20's. I wanted to keep it as stock as possible...but, if wishes were horses... But, my street racing days are over so this car will be more "show" than "go". Can I spend $500-$600 on a Hurst -yes. Do I want to - no. I definitely want to keep my console shift plate. The levers are not upside down and all 3 are factory. I can move the reverse and 1/2 levers with the rods off but 3/4 won't move. That's about all we can do now and I'll get back to you in a few weeks. Thanks.
     
  11. Magicman7

    Magicman7 New Member

    You guys and Grumpy's are GREAT! When I first reinstalled the transmission
    I couldn't find a gauge to get the gates in neutral so I made my own.
    The gate hole is not round, it is a horizontal rectangle, 1/8" X 5/8".
    The first gauge was too wide and the second was too narrow.
    When Rich talked about adjusting the rods and said, "...Get picky here. - this is the most important part.",
    I reassessed the accuracy of my gauge and ground it slightly more narrow. It worked. I shortened the
    1/2 rod 4 turns and the gear shift wouldn't move AT ALL. I decided to "give up" temporarily
    until my rebuilder could heal and help. I lengthened the 1/2 rod 3 turns and decided to try the
    gear shift one more time for the helluvit. It shifted smoothly through all 4 gears!!! I removed the jack stands
    and lowered the tires to the concrete and the 1/2 would not shift and 3/4 stumbled into gear.
    I lengthened 1/2 one more turn and 1/2 and 3/4 shifted again. No, it's not as smooth as a new Hurst
    but I only need to get the car on the road, pass state inspection, and licensed. I can consider a Hurst later.
    Thank you guys, I couldn't have done it without you!
     
  12. chromebumpers

    chromebumpers solid fixture here in the forum Staff Member

    Move over Brian:rock:
     
  13. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    I did not think it was in the Muncie 4 internal.
    I have rebuilt at least 20 of them in my time.
    1st One I rebuilt I was 17 years old in 1987.

    My 70TA is a Muncie 4.
    I rebuilt it last 2003.

    You can not get the sidecover on at all if you assemble the trans incorrect.

    Go Road racing or drag at the strip and that factory shifter will let you down.
    Race a Dodge RB440 or Hellcat when you really need to slam bang those gears on the street.
    Dodge will win because you missed a gear especially 3rd gear.
    Hurst Shifter Needed.
     
  14. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    Dont ever think a Vintage 440 Mopar Muscle Car will not Run.
    My Bud Bob Had 600 Hp with his old one back in 1998.
    It pissed him Off bad I walked away 10 car lengths ahead with my 1970-1/2 RAIV455.
    But off the line it was neck to neck.
    1-2.
    2-3.
    Shifts by me had to be perfect.
    3-4 wound out.
    4th gear I walked away.
     
  15. chromebumpers

    chromebumpers solid fixture here in the forum Staff Member

    Yes, that 2 - 3 shift is real sloppy in a a factory shifter, it cost many a race. It does help a little with placing the rods in the second hole on the shifter links as I posted days ago.
     
  16. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    No too many guys running Muncie 4's on Forums, or they never post alot the guys that do.
     
  17. chromebumpers

    chromebumpers solid fixture here in the forum Staff Member

    I meant the occasional macho traffic light racing, not anything organized or setup by repeat racers
     
  18. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    Yes. it is what happens typical with Corvette owners & muscle car owner.
    Stoplight racing or showing off for a few seconds.
     

Share This Page