The History: Bought this car (94 LT-1 6spd ) a few years ago now. It had a spacers between the engine and bellhousing. Originally, we thought that the car may have had the wrong flywheel. We were never able to figure this thing out until the engine developed a problem and we took it all apart.

Upon reassembling the drive train the mechanic discovered that the wrong clutch was in the car. The pressure plate was too thick to put things back together properly or at least put it back together without the spacers.

The only thing I can think of is that the clutch may have been for another version of the C4. Perhaps it fit a L98 with a 6 speed??

Looks like NAPA part number for a 94 clutch is NNCMU701461
NAPA part number for a 91 clutch is NNCMU831

Anyone else ever had a mess like this? It cost me a extra ton of money to correct this problem...

 

Geez, no responses.

 

Hey, its only been an hour and a half, patience my friend. Makes me not want to help.

The only difference between the 91 and 94 clutch sets is the throwout bearing ID. everything else is exactly the same.

GM also went to a very slightly narrower bellhousing.

Did the clutch look different than what you reinstalled? Most of the standard sprung hub clutches won't clear the pressure plate. The ZF clutch is non-sprung.


I have a p/n guide on my work computer with all the interchangability, I'll try and get it on Friday.

 

I was in a panic mode. The mechanic popped me and I am going to stop pmt on the check this am until I sort this thing out. He also cracked my windshield and my top. The car "flexed" on the lift he said. (Thankfully, I took the good top off the car...).

Just a little pissed.... Paid $2093 to have him install the new engine and replace the clutch. On top of that the hew clutch rattles.

Thanks for the response Central!!! I do appreciate it!

 

Is it possible he it the windshield or top with the motor/trans? Any chip damage or point of impact?

I've never heard of either breaking on a lift. I've put mine up on jackstands probably 75 times in the same place a 2-post lift would support it by. Hell, I've had it teetering diagonally, dropped it from a foot high with the quick release jack, etc. And I presume hard driving will do way more to flex the chassis than lifting it ever will.




If it was assembled with spacers, he would have realized that on disassembly. If he's shimming crap together with washers, then get your car out of there asap. You can't always get the car though without paying first (and disputing later). Mechanics can hold a mechanics lien on it until you pay.



What status is the car in now?

 

get the car first, then put stop pmt.

 

Holy @#$!

I'm afraid to ask, who's going to take financial reponsibilty for that dilemma?

Regardless, I feel your pain man. Hope they resolve it all to your satisfaction.

 

I agree - this'll give ya some leverage.............

 

if ya ask me $2000 for a motor swap and a new clutch installed sounds pretty high to me i had a motor put in and had the trans switched from an auto to a muncie 4 speed for half that in a trans am i had thats motor clutch clutch linkage pedals and so on. is there more to the job then motor install and clutch? i hope the price includes the new clutch at least. maybe its just me but i think the price is kinda steep. if it was me id insist he fixed what he broke. i highly doubt it broke the way hes claiming and if it did id be hugely suprised. if it flexed when he lifted it id havta assume he didnt lift it properly which would be his fault not yours.

 

There are a few answers to your clutch question , I have read and experienced some , repeat some Corvette C-4 mechanics think you can install Camaro style Flywheels in a LT1 Corvette. Here is what I have found the Camaro flywheel (half the price of the correct Part) is .090 thicker then a Corvette LT1 flywheel , when installed in a C4 (without machine work) it will not let the clutch disengage all the way causing hard shifting and gear grinding. If this has happened some shade tree Mechanic may have installed spacers between the engine and Bell-housing to repair the clutch travel , just a thought , if any of the old clutch parts have Part# try and cross reference them back to a Camaro.

let me know how you make out....

Desert

 

Take the very best pictures you can of the damage. They may be useful in court if need be. Also, see if you can find pictures of your car BEFORE the damage was done. This will help prove it was new damage. If you stop payment he will most likely put a lien on the car.

 

Spacing out the bell housing won't affect the clutch at all. The only thing it will do is move the clutch fork pivot ball.

I honestly can't think of a reason why you would space the bell housing away from the engine. I seriously doubt that was done to your car though. Think about the logistics of something like that:

If you move the bell housing back, you've moved the transmission back so-

-The shifter is in the wrong spot
-the C-beam is the wrong length
-the drive line is the wrong length
-I seriously doubt the slave cylinder line is long enough to attach the slave if the mounting studs are 1 inch further backward
-If you moved the transmission back an inch, the input shaft would not seat into the pilot bearing. After some hard shifts/launches or high RPM, I would think you'd break the input shaft

And I am sure there are a ton more issues. There's really no way that was done to your car. Or if it was, I can't figure out any reason that would require such actions.

The clutch is independent of the bell housing. Think about how it operates:

The flywheel is bolted to the crank, which the bell housing has no bearing on.

The clutch plate is smashed between the flywheel and the pressure plate, the pressure plate is bolted to the flywheel, so the bell housing can't affect it either.

The only affect moving the bell housing reward would have would be to pull the input shaft away from the engine, but since the shaft is splined it's entire length, and the clutch is designed to 'float' on the shaft, that would have no bearing on the clutch either.

If you really do have spacers moving the bell housing away from the engine, I would suspect the bell housing itself. Perhaps at one time it was machined down for some reason. If that were the case, then you would have to shim it rearward in order to make everything line up properly. Is there any welding on the bell housing? Maybe it was cracked and when it was repaired one face needed to be cut true again?

It is very odd, and truthfully I almost wish I was there to see it. Oddities like this really intrigue me. Trying to figure out why someone did what they did when there is no apparent reason is really quite interesting to me. Were you able to verify the spacers were actually there, or is it something the mechanic told you? If he said they were there to correct some misalignment of the clutch, he's lying, or he doesn't know anything about clutches.

As far as the windshield is concerned, the shops insurance will cover it. The shop might complain and tell you you're out of luck, but don't give up. C4 glass does not crack when the car is lifted properly. Hundreds of them are lifted on a daily basis with no problems. His excuse is just that, an excuse. Don't buy into it, stick to your guns, and don't let them push you around.

Give us the complete scoop on the spacers and transmission issues and we'll see if we can't figure out what the Hell is going on.

 

Sorry to disagree with you my friend,
posting just said "Spacers"

Here is what I have found , when a Flywheel that is too thick is installed , it moves the whole clutch assembly deeper into the bell housing. this cause the fork to be at a very extreme angle and sometimes even hit the pressure plate. this causes the clutch fork to move the opposite way . now the problem is that the slave cylinder runs out of travel before it totally dis-engages the clutch causing grinding. so by adding a washer on each belhousing bolt it moves the fork back to its original , or closer to its correct angle.

I'm not trying to start any problems , just trying to tell you I have seen many mant Mickey Mouse repairs by so-called Mechanics over the years.

PS:Shop insurance should pay for any windshield damage!!!!

Desert