Clutch inspection plate - need advice

[Ed S.]

Talking about a 64, L76, manual trans, all stock. I removed the starter & clutch inspection plate in search of a fluid leak. (I identified the source of the leak, the trans countershaft - repair to be done at a later time).

The inspection plate I took off the car was damaged - screw holes were all torn up - it was an original design, no tabs. I got a replacement from LIC - flat, no tabs. I installed it today, started the car and the noise was immediately hellacious -- scared the daylights out of me. Prior to installing it I checked it for flatness on a cast iron table table saw - it was good. I didn't do any other repairs or operations on the car so I am very confident that the noise is the inspection plate.

From various threads on related issues I understand that this inspection plate can be real noisy if it makes contact with the crank shaft and the fix is to remove it and bend it slightly. Please confirm that I would bend the top center out - towards the front of the car - a fraction of an inch. Is that correct?

For what it's worth, I am including a pic of the inspection plate I installed - this is an LIC pic. I noticed that the Paragon plates are different, they have the 2 tabs - would it be advisable to just get one with the tabs?

[Joe L.]

Re: Clutch inspection plate - need advice

Talking about a 64, L76, manual trans, all stock. I removed the starter & clutch inspection plate in search of a fluid leak. (I identified the source of the leak, the trans countershaft - repair to be done at a later time).

The inspection plate I took off the car was damaged - screw holes were all torn up - it was an original design, no tabs. I got a replacement from LIC - flat, no tabs. I installed it today, started the car and the noise was immediately hellacious -- scared the daylights out of me. Prior to installing it I checked it for flatness on a cast iron table table saw - it was good. I didn't do any other repairs or operations on the car so I am very confident that the noise is the inspection plate.

From various threads on related issues I understand that this inspection plate can be real noisy if it makes contact with the crank shaft and the fix is to remove it and bend it slightly. Please confirm that I would bend the top center out - towards the front of the car - a fraction of an inch. Is that correct?

For what it's worth, I am including a pic of the inspection plate I installed - this is an LIC pic. I noticed that the Paragon plates are different, they have the 2 tabs - would it be advisable to just get one with the tabs?

Ed------

I would not even consider using a bellhousing lower cover without the integral clips. Sometimes, intentions to correctness just go too far. GM added the clips to the bellhousing covers a long time ago and they did it for a very good reason. You have discovered the reason.

[Mike M.]

Re: Clutch inspection plate - need advice

I too have experienced the noise you witnessed--sounded like a pair of skeletons having intercourse on a tin roof. saint Michael

[Ed S.]

Re: Clutch inspection plate - need advice

I too have experienced the noise you witnessed--sounded like a pair of skeletons having intercourse on a tin roof. saint Michael

And they are wearing a lot of metal jewelry!

So, can the non-tab plate be "adjusted" to correct the problem or is it hopeless? Which way do you "persuade" the plate up at the top, out towards the front of the car or back towards the rear. I'm thinking towards the front, just a bit.

[Russ S.]

Re: Clutch inspection plate - need advice

Yes bend it towards the front.

[Gene M.]

Re: Clutch inspection plate - need advice

Ed------

I would not even consider using a bellhousing lower cover without the integral clips. Sometimes, intentions to correctness just go too far. GM added the clips to the bellhousing covers a long time ago and they did it for a very good reason. You have discovered the reason.

[Perry M.]

Re: Clutch inspection plate - need advice

Has the clutch or flywheel ever been removed? How did the original plate get ruined? Check the clutch/flywheel bolts to make sure they are not too long. Don't ask me why I ask.

[Edward B.]

Re: Clutch inspection plate - need advice

So, can the non-tab plate be "adjusted" to correct the problem or is it hopeless? Which way do you "persuade" the plate up at the top, out towards the front of the car or back towards the rear. I'm thinking towards the front, just a bit.

Bend it away from the side where the paint was scraped off, but better yet. replace it with the tabbed version.

[Ed S.]

Re: Clutch inspection plate - need advice

SUCCESS! I removed the inspection plate, found that the sheet metal at one corner up in the vicinity of the small semi circle was actually bent back over. I "enlarged" the diameter of the upper half circle by about 1/4 inch, straightened the sheet metal and then bent the sheet metal around the semi circle back (towards the front) just a bit. Reinstalled everything - Perfect! No noise. Thanks to all for your advice and comments. I will likely replace that shield with a tabbed one sometime in the future but for now my fix is working fine -- fingers crossed.

[Joe L.]

Re: Clutch inspection plate - need advice

Agree 100%
When did GM make the change to tabs?
I’ve never used the no tabs design thinking there should be something there to secure a floppy piece of sheet metal. Can’t see it anyway but if it rattles ya sure will hear it.

Gene------


It depends on which bellhousing is involved. The cover for the 12-2/4" flywheel bellhousing used for all 63-68 Corvette small blocks as well as 65 L-78 and 67-69 L-88 was originally GM #3788422. This cover had no clips. This cover was replaced in 1975 by cover GM #354497. This cover has the clips. It's still available in SERVICE.

The cover for the 14" flywheel bellhousings used for most 1966-74 big blocks except L-88 and most 1969-75 small blocks except ZR1 was GM #3843943. This same cover was used throughout the period in both PRODUCTION and SERVICE. However, the clips were added sometime about 1975 but the part number never changed. It's still available in SERVICE to this day.

1976-81 Corvettes with bellhousing for 14" flywheel used cover GM #340252. This cover always had the clips. It's no longer available from GM.

[Joe L.]

Re: Clutch inspection plate - need advice

SUCCESS! I removed the inspection plate, found that the sheet metal at one corner up in the vicinity of the small semi circle was actually bent back over. I "enlarged" the diameter of the upper half circle by about 1/4 inch, straightened the sheet metal and then bent the sheet metal around the semi circle back (towards the front) just a bit. Reinstalled everything - Perfect! No noise. Thanks to all for your advice and comments. I will likely replace that shield with a tabbed one sometime in the future but for now my fix is working fine -- fingers crossed.

Ed------


There are only 2 conditions for the covers without the clips: 1) just barely not causing interference and noise, and 2) causing interference and noise.