DansYellow66

Bummer - got my rebuilt Muncie in today and fired it up and have clutch vibration - rattling as I let the clutch out. Haven't had to deal with this since I got rid of my 70 GTO about 1975. I only drove it around the block but it seemed to be getting worse at each start from a stop so I guess I have no choice but to start pulling it apart again. It vibrates like clutch chatter as I start letting the clutch out in first but also get sort of a rattling/grinding noise while clutch is engaging.

Transmission seems to be fine - shifts fine, no strange issues once the clutch is out and I'm moving.

Pressure plate - new 11 inch McLeod. Fingers were all sitting even in height. Wiped down lacquer thinner & brake cleaner
Flywheel - new Ram 18 lb aluminum - Wiped down with lacquer thinner
Disc is used but only 2700 miles on it. I was careful not to handle it by the friction material and I lightly sanded to bust up any glazing.
Pilot bushing - new non-metallic
TO bearing - new Mcleod. No noise that I noticed over the sidepipes with pedal down until I started to feather the clutch to start.
Bellhousing - stock. Checked it with a dial indicator years ago and from memory it was under .004 inch of center.
Fork - used 2700 miles - looked good.
Installed transmission with dowels - slid right in once engaged in the splines. Clutch & flywheel torqued down - everything else tight.

I have two suspicions. 1 - The pilot bushing literally popped in place by hand after storing in freezer for an hour. I expected to at least have to give it a light tap into place. It seemed solid and didn't move but I didn't mess with it much. Possibly it's loose. 2 - the TO bearing slipped off the fork while maneuvering the transmission into place. I thought I was careful to get it installed correctly with the fork shoulder and spring fingers all in the grove but possibly one of the fingers is out.

After that all I can think of is some form of pressure plate defect.

Any thoughts?

wmf62

you didn't put the disc in backwards? it would do exactly as you describe....

Bill

DansYellow66

I hope not. I think it can only go one way - protruding hub to the rear.

Jackfit

I thought that about my distributor gear, it can only go in one way, WRONG!....

Jack

Ps know your pain after all the work..makes a grown man wont to cry

wmf62

I have made that mistake myself , the springs towards the engine; the springs will hit the flywheel mounting bolts....

Bill

Plasticman

Non-metallic pilot bushing? Too loose could be an issue.

But I agree with the others on the reversed clutch disc as likely.

God, I hate do overs........

Good luck,

Plasticman

wmf62

worse case scenario...

Bill

DansYellow66

Well, I won't discount anything yet but I don't think it's possible to install the disc backwards with that aluminum flywheel. I don't think there's enough room for the hub to go there - the disc would be 1/2 inch off of the flywheel surface. This is not the right number flywheel in this ad but it's other wise the same basic flywheel I installed except for earlier generation engines.

https://www.summitracing.com/parts/r...FQ-OaQodHdwC2w

Wouldn't the disc be sprung against the pressure plate and the hub hung up on the flywheel and bolts and never release in neutral? It was releasing fine with the clutch pedal pushed in.

I'm still leaning towards the TO Bearing being crooked on the fork with one spring finger in the grove and the other outside and it's releasing the fingers on the plate unevenly and cocked so that it's dragging on the bearing retainer.

Hard for me to figure - this is about the 4th time I've had the transmission and clutch out of this car and it's always gone back together fine in the past. Lucky me. It's probably going to have to sit awhile until I can take it back apart - I have some other stuff I have to get done first.

Thanks

wmf62

well, you won't know til you know... whatever it is.... and, whatever it is is VERY frustrating, especially if you have a full bellhousing like was used on the C2s and can't see what's going on... (that's what I like about the open bottom bellhousings used on the C1s

the pictures certainly were worse case examples and a lot would depend on how the flywheel and disc are made; but in my case the springs were just touching the bolt heads and were not enough to keep from disengaging.

my thoughts are with you

Bill

DansYellow66

Thanks Bill.

I'll own up to whatever I find inside when I can get back to it.

vette61

Not sure what setup you have but if you have a dust cover just in front of the flywheel (engine side) check to see if the flywheel bolts are touching it and making the noise. Do a search on the forum, lots of info about this issue.

wmf62

the open bottom C1 bellhousing dust covers run this 'close'....

Bill

DansYellow66

I'll check but new flywheel is thicker than the old one and there isn't any noise when the clutch was pushed in which would have loaded the crank against the thrust bearing. Also I have a shudder/chatter with it. The short drive I took didn't allow much diagnosis but it didn't exactly feel like regular clutch chatter I've experienced in other cars.

I shouldn't have posted this thread as there is really is no ultimate answer until I start taking it apart again and examine it. Guess I was just anxious over what I will find.

Thanks

wmf62

no regrets... you might have gotten an "aha' moment...

and this has been a heck of a lot better than some of the postings that want advice/suggestions and continue to take none and continue to 'what if'... I get disgusted with them (and there are a few running right now....)

Bill

426 Hemi

Couple years back I had a throwout bearing that was off center----the surface that touches the fingers was grating up/down--side to side on the fingers. Put out a weird racket. Was a new bearing that came in a Luk kit.

pop23235

Before digging too deep, remove the clutch release rod and the boot around the clutch fork. If you have an inspection camera, all the better. If not, twist the fork and see if it seems normal or hung on only one side. I think your thoughts about this are most likely.
Or, the disc just needs a bit of wearing in.

6T7L71CPE

I used the "RAM Billet Steel Flywheel 1523" for my 383. I saw this warning on this and maybe others so I checked for clearance. I'm using the stock LUK clutch.


"Performance and SFI-approved flywheels must be used with performance clutch discs only. Use of a stock-style clutch disk with a performance flywheel will often result in insufficient operating clearance between the disc hub and flywheel bolts."

wmf62

see, an "aha" moment (or at least a smoking gun...)

thanks


Bill

DansYellow66

I didn't notice that on mine but maybe I missed it. I will take a look at the papers.

True - some new things to consider. I am running a RAM flywheel, McLeod pressure plate and a Centerforce disc. What could go wrong.

DansYellow66

I actually tried this today with my little camera but I have a hard time ever seeing anything with it. I did find that I forgot to tighten the lock nut inside on the adjustable fork stud and it was a little wobbly. That could be contributing to some shudder but I doubt it's the major issue. It seemed that one of the lower fingers on the fork was out of position on the TO bearing but I couldn't get a clear picture. I could see the upper one reasonably well and it looked OK.