Shifter lock up question...
Thread Starter
Moderator
Joined: Jun 1999
Posts: 7,117
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From: Dove Mountain Arizona
Shifter lock up question...
This tranny was completely rebuilt (less than 1500 miles on it). It's a Muncy M21. Yesterday was the second time it locked between 2nd and 3rd. I was easily shifting from 2nd and the shifter stuck in the neutral area but the tranny was still in second gear. As per the first time I got under and put a long 1/2" wrench on the rearmost shifter bolt. With a little playing with it and also moving the center bolt it finally let loose and I was able to use it again. It has a Hurst shifter but don't know about the linkage. I do know it has 3 bolts that attach it and one of the bolts is trapped under the linkage itself (hard to get to). Gonna get under tonight, just want to know if it could be just a linkage lockup problem and what to look for. Can't believe it would be a lubrication problem but just do not know. Thanks... :steering:
Melting Slicks
Joined: Oct 2001
Posts: 2,740
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From: Marblehead MA
Re: Shifter lock up question... (MasterDave)
Most likely its the shifter. I just had the tranny (M20) in my 63 gone through and the origional shifter couldn't be adjusted to work, so I wound up getting a Hurst. No problems since. Still, I have the origional but it definatley needs to be rebuilt. :smash:
Thread Starter
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Joined: Jun 1999
Posts: 7,117
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From: Dove Mountain Arizona
Re: Shifter lock up question... (Denney)
I told the rebuilder to adjust it prior to returning it to me and it's been fine for the past couple of years (I think anyway) but it may be time to re-do it. Gonna look under tonight for anything obvious. And I suppose someone on the forum could hook me up with the how-to for adjusting? :D Again, not sure if the whole assy is Hurst or just the shifter lever, how do I tell? If the adjustment procedure is the same, it doesn't matter though. Thanks guys... :cheers:
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
Re: Shifter lock up question... (MasterDave)
The adjustment procedure is basically the same. If you have a Competition Plus shifter (Hurst) you will see a stop bolt with a lock nut on both sides of your cage that goes around the shift levers. I've never seen a 4 speed lock up because of internals in the transmission but then I've only had a dozen of them. My money is on the linkage adjustment.
Mike
Mike
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Joined: Jul 2001
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From: Thornton Co
Re: Shifter lock up question... (MasterDave)
Dave,
I would doubt the hurst is the problem, they are pretty bullit proof. If it is a Hurst you can adjust it pretty easy. there is a hole going through the bottom of the shifter that you can stick a drill bit in when in nuetral, then you adjust the linkage rods so that your transmission levers are in there nuetrel positions. It doesn't take alot of adjustment either way to make to much pressure on the tranny levers so make sure they are right in the middle. When you get those adjusted take out drill bit or whatever you use and adjust your throw stops.
You may also have a weak linkage rod, this happened to me and it kept bending just enough to throw off the whole package.
But my best one is when I had my original shifter in and I actually got a rock kicked up into my shifter locking my into third gear, that sucked big time. :mad
Kurt
I would doubt the hurst is the problem, they are pretty bullit proof. If it is a Hurst you can adjust it pretty easy. there is a hole going through the bottom of the shifter that you can stick a drill bit in when in nuetral, then you adjust the linkage rods so that your transmission levers are in there nuetrel positions. It doesn't take alot of adjustment either way to make to much pressure on the tranny levers so make sure they are right in the middle. When you get those adjusted take out drill bit or whatever you use and adjust your throw stops.
You may also have a weak linkage rod, this happened to me and it kept bending just enough to throw off the whole package.
But my best one is when I had my original shifter in and I actually got a rock kicked up into my shifter locking my into third gear, that sucked big time. :mad
Kurt
Thread Starter
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Joined: Jun 1999
Posts: 7,117
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From: Dove Mountain Arizona
Re: Shifter lock up question... (MasterDave)
Thanks guys, I pulled the linkage 'how-to' off the Mr. Gasket site and will check this evening. Too tired yesterday........ :yesnod:
Thread Starter
Moderator
Joined: Jun 1999
Posts: 7,117
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From: Dove Mountain Arizona
Re: Shifter lock up question... (MasterDave)
Got the car up on jacks last night and slid under to take a look. That's about all I could actually do is look. The mechanism is up above the crossmember the tailpipe winged attach plate and btwn the tailpipes. All I could relaly do is spray lots of WD-40 up there to clean off any dirt/debris. Looks new now. Interesting though (I remember this when the rebuild was progressing) that there was a slot cut in the winged tailpipe hanger bracket to allow one of the flat shift arms (the ones hooked to the trans fork bolt) to go full travel. Appears to be the rearmost arm. This slot is like 3/8"W X 1.5"L and doesn't look to me to be 'factory' at all. Does anyone know if this slot was needed when changing to a Hurst mechanism or not? :confused:
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