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Muncie issue

Kid_Again

Well-known member
Joined
Jul 6, 2004
Messages
1,171
Location
NJ - Which exit you from?
Corvette
65 SB Roadster, 66 BB Coupe
OK, so when I had the current Muncie behind the original 427, I had no problems. It was rebuilt by Ed Hartnett. It shifted flawlessly.

Out goes the old 427, in goes a zz440 and the trans has never been the same since. Grinds between 3/4 and sometimes wants to pop out of 2nd - but no grinding.

I HAVE DONE EVERYTHING (but pull the side cover). The shifter rods are perfect. I have a lift and can take all day on that one. I have pulled the transmission and gone all the way to the pressure plate - checked everything. I also have a CenterForce clutch and have meticulously checked for runout. Less than .005" Correct throw out bearing. Correct clutch fork. Hell, it worked perfectly with the 427.

The one thing I noticed was that when I pulled the tranny this time, I noticed that the tail was sitting down low on the trans crossmember. I had added shims to the rear mount to equal the thickness of the exhaust hanger that used to be there (I now have side pipes), as I've alwys done. But it seemed the trans was sitting too low in the rear. I removed the shims, the trans does sit higher and it does shift much better but it still has a bit of a grind between 3/4.

I DO NOT beat this car. With all the money that I have into it, there's no way I'm going to speed shift.

What do you think?????
 
You DO NOT BEAT this car. That is a crying shame. I would crucify it every time I got into the driver's seat. That's why you build a big HP car. Now on to the question.

Sounds like you have checked about everything I can think of. Only things you didn't mention is if the pilot bearing/bushing has been checked for proper fit against the input shaft of the transmission and whether or not the clutch disc is completely released when the clutch is engaged.

Usually, worn out synchro assemblies/blocker rings can cause the grinding and popping out of gear you are talking about. Does it pop out of gear under load?(it shouldn't) or when you are letting off (more common to pop out of gear into neutral).

As far as the 3/4 grind, is it both up and down or just in one direction of the shift? If the clutch disc is not fully released between the flywheel and cover assembly when shifting then the synchronizer assembly is being strained additionally as the energy from the motor is still in play. Same thing would apply if the input shaft is forced into the pilot bearing/bushing either by diameter or by jamming into the front of the splines.

Rich
 
I agree on the pilot bushing or did it have a bearing? If bearing then the bellhousing has to be indexed to align the input shaft.
 
Sorry for the troubles ,seams you can never win with these things something is always giving us troubles

I had the trans done in the 66 buy Ed. year ago

I would call him and explain whats happening and ask his advice.

Funny thing is he did my trans awhile ago I made my deal at Corvettes of Carlilse and shipped him my trans

Every year when I go by his booth he always says hello and remember my name.
It always makes me feel good when I see him and he actually remembers my name.

I always pride my self on great customer service and no matter how hard I try I just dont remember everybodies name

Best of luck with the repair
 
...all good advice...don't know why I didn't think of calling Ed..

...to answer the questions as best i can.....i have a pilot bushing and the input shaft fits perfectly as far as i can tell....i used the shoplight to look at the bushing and it has even wear and is prefectly concentric...the input shaft shows no wear

....the trans will pop out while accelerating in 2nd gear, doesn't do it often but only in second gear...the grinding occurs only when going from 3->4

....when i had the thing apart, i looked at the flywheel and it looked evenly worn (milled flat about 1k ago), the friction plate was evenly worn, even measured the thickness around the periphery at 6 points and the readings were essentially the same...

....i agree that it sound like the synchros are gone but to have ABSOLUTELY no problem with the 427 and then to have the problem right out of the box with 454?


only me:W


thanks for the replies
 
Nope its just jealous you are spending so much time on the small block car and wants some attention. Just be glad you only have one Wife.;LOL



....funny you should say that, when somebody asks me about the cars i tell them it would be cheaper to have mistress;shrug
 
Are you sure your 1/2, 3/4 linkage adjustments are neutral happy?
 
OK, will check AGAIN :hb
 
I recently had a problem with my muncie popping out of first. The gears were brand spanking new - all of them - had about 1000 miles on the setup when this started happening. Well... I got underneath it last night and found the problem.

My 1/2 linkage was adjusted to be as short as possible. This isgoign to be hard to visualize but this is the rod that attaches to the lever on the outside (front and back) through the use of a clevis. Since I had it adjusted as short as possble, the rod actually stick too far through the clevis and interfered with the shift lever as the lever rotated into position. I ground about 1/16 of an inch off the 1/2 lever and and all is well.

Brian
 
yup, makes sense..i can visualize that....well, MAYBE there is something wrong with the linkage;shrug
 
If.........

What you said in your first post is on the money, my money is in the shifter/linkage. What kind of shifter is it, how much wear and tear, age? If the shifter plates are worn, the center bolt or where the rods attach can all make a difference as can one turn of the adjuster. I'm sure you have the neutral tool for the shifter to start lining everything up and you know what you're doing. Didn't you have trouble before with a shifter at VNV's? The bushings, everything makes a difference and Ed sells the rebuild kits for all of them.
 
rowdy1....the shifter is a hurst competition plus with maybe 3k on it....never had a problem with the shifter and trans when i had the original 427 in the car....first happened when i replaced the 427 with the zz440:eyerole
 
Joe,

When I first installed the Richmond behind the 502, I found that even the slightest deviation from "exact" meant that I lost the ability to shift into at least a gear or two.

Even with the alignment pin, getting the adjustment just right was like trying to part the fuzz on a peach. ;)
 
Square 1

If everything was fine before the switch, you may be overlooking the obvious. I'd drop the linkage rods, line the plates up with the tool and start there.
 
OK guys, I acknowledge that you know what you're talking about. I'll put 'er back up on the lift, first take pictures of what I currently have, take ALL the rods off and start all over again.

My plan is to finish the sb and get that on the road. Then make sure the bb is road worthy and drive it downa' shore over an upcoming holiday weekend and call VNV over. At that point, we swap intakes and install the newly refinished tripower setup which i JUST HAPPENED to take down the shore last weekend. The manifold was rough when I bought it at Carlisle and this time I stripped the old powder coat and re-coated it with Eastwood's Sparkly Silver. You can imagine how VNV reacted to that - man, he LOVES bling:drool:
 
:m Yup, it was obvious.

All the while, I paid attention to the 3/4 rod and it was really the 1/2 rod.

Not sure how this happened because I'm certain that I didn't futz with the linkage whenI swapped engines.

ANYWAY...With the car up on the lift and moving the 3/4 rod forward, it was obvious that it wasn't going all the way into 3rd gear. No binding, clearance all around. WTF?

This time, I took the Hurst instructions out into the garage and eyeballed everything. If you look at the shifter levers that attach to studs on the shifter forks, they have a definite pitch. The front (3/4) lever moves the rod AWAY from the tranny while the rear (1/2) lever moves the rod TOWARD, tranny. I suppose that's to give the rods enough space internally to move without hitting each other. OK, the 3/4 lever and rod look prefect but the 1/2 lever is put on backwards:eyerole . That will make a substantial difference as the key slot on the lever is angled off the vertical. So, no matter how carefully I shifted into 3rd, I took a LITTLE bit of 2nd with me. Idiot.

SO, I just flip the 3/4 lever and button it back up, right?

No so fast synchro breath. Mounted correctly (ABSOLUTELY CERTAIN), the lever rubs against the tranny case when I tighten down the nut. ****. SO, I have to grind away at the back of the lever to clear the case. It finally fits.

Haven't taken it on the road yet because IT'S STILL RAINING but the 1/2 adjusting nut went out more than a few turns and now the trans feels much more solid when dry shifting.

Oh well.
 
I know. I know.:eyerole
 

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