Finally installed 'match balanced' flywheel + PP= vibration :(
Thread Starter
Race Director
Joined: Dec 2002
Posts: 10,233
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From: Baltimore suburbs Maryland
Finally installed 'match balanced' flywheel + PP= vibration :(
Heres my end to this story: http://forums.corvetteforum.com/showthread.php?t=963934
I finally got around to doing my car and put in the lightened flywheel that I had matched balanced to my old flywheel. They drilled out 3 small spots on the flywheel and said that the pressure plate was pretty far off. They welded a weight about the size of 10 dimes stacked together on the pressure plate.
I finally put my car back together enough to start the car up (open manifolds ah yea). I was doing 3 things 1) visually check the pressure plate for any "wobble" which may have caused my slave cylinder to die
2) check for vibration and 3) heat up the motor oil to change it
Bad news to report is that there is vibration at around 2000 RPM's. Cruising RPM. Its not really that bad but its enough to be noticeable. I think I'm going to grind that weight off and hopefully it'll loose the vibration. I really wonder whats up with this, after taking the time and effort to get it match balanced and it vibrates. Ugh. I dont think the OEM assembly vibrated like this but honestly I cant remember.
I finally got around to doing my car and put in the lightened flywheel that I had matched balanced to my old flywheel. They drilled out 3 small spots on the flywheel and said that the pressure plate was pretty far off. They welded a weight about the size of 10 dimes stacked together on the pressure plate.
I finally put my car back together enough to start the car up (open manifolds ah yea). I was doing 3 things 1) visually check the pressure plate for any "wobble" which may have caused my slave cylinder to die
2) check for vibration and 3) heat up the motor oil to change it
Bad news to report is that there is vibration at around 2000 RPM's. Cruising RPM. Its not really that bad but its enough to be noticeable. I think I'm going to grind that weight off and hopefully it'll loose the vibration. I really wonder whats up with this, after taking the time and effort to get it match balanced and it vibrates. Ugh. I dont think the OEM assembly vibrated like this but honestly I cant remember.
Thread Starter
Race Director
Joined: Dec 2002
Posts: 10,233
Likes: 21
From: Baltimore suburbs Maryland
yeah I forgot to mention that- the flywheel has the little dimble where it only goes one way that matches the position on the crank. The pressure plate was paint marked to match the position. I even kept the bolts the same position.
Im going to cut that weight off and hope that it makes the vibration less, but theres a chance it may be more.
Im going to cut that weight off and hope that it makes the vibration less, but theres a chance it may be more.
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
We put a new Z06 clutch in Sidestep's '01 a few weeks ago. We transferred the weights from the original flywheel to the new one. He had a slight vibration in it after trying it for a few days so he popped the weights out of the flywheel and the vibration was gone.
Le Mans Master
Joined: Apr 2002
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From: Glendale NY
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16-'17-'18- '19
Cut the Weight
________________________________________ ____________________
Im going to cut that weight off and hope that it makes the vibration less, but theres a chance it may be more.
________________________________________ ____________________
Is it possible to cut a portion of the weight off ? Cut off maybe 1/3 of the weight and see if it gets better, or, worse
Im going to cut that weight off and hope that it makes the vibration less, but theres a chance it may be more.
________________________________________ ____________________
Is it possible to cut a portion of the weight off ? Cut off maybe 1/3 of the weight and see if it gets better, or, worse
Last edited by 6SPD98; Jan 2, 2005 at 09:16 PM.
Melting Slicks
Joined: Oct 2002
Posts: 2,200
Likes: 0
Originally Posted by Patches
We put a new Z06 clutch in Sidestep's '01 a few weeks ago. We transferred the weights from the original flywheel to the new one. He had a slight vibration in it after trying it for a few days so he popped the weights out of the flywheel and the vibration was gone.
Thanks for all the labor and advice Ed
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Melting Slicks
Joined: Oct 2002
Posts: 2,200
Likes: 0
Originally Posted by eRiCdWoNg
Well I cut the weight off and sure enough, it spins better. So much for match balancing. I'm STILL confused and havent found a definate answer yet.
Drifting
Joined: Sep 2004
Posts: 1,727
Likes: 19
From: Carson City, NV
ah crap!.....does this mean I'm in for a balancing PITA when I install my new Exedy Twin clutch/flywheel setup? Do I need to get it balanced? or match balanced against my factory clutch assembly? 
John
John
Drifting
Joined: Apr 2001
Posts: 1,337
Likes: 52
From: Wentzville, MO.
Originally Posted by Cscokd
ah crap!.....does this mean I'm in for a balancing PITA when I install my new Exedy Twin clutch/flywheel setup? Do I need to get it balanced? or match balanced against my factory clutch assembly?
John
John
Le Mans Master
Joined: Aug 2002
Posts: 8,472
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From: Houston TX
St. Jude Donor '11
Originally Posted by eRiCdWoNg
Bad news to report is that there is vibration at around 2000 RPM's.
Wow, that really blows considering all the effort you put in to get it right. The only thing I can see that may have gone wrong is that you had the new flywheel balanced to the old flywheel rather than having the new PP and FW as a unit balanced to the old FW/PP unit.I may be wrong but it sounds like things were spun separately.
Team Owner
Joined: Mar 1999
Posts: 28,753
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From: San Jose/Bear Valley CA
CA Events Coordinator
Sorry to hear you are having a problem.. It really doesnt make sense to have a new assembly ballanced perfectly to the old one then have a new vibration? The only thing I could think of is... they didnt really ballance it to your old one. 
VR
VR
Advanced
Joined: Jun 2004
Posts: 61
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From: Land O' Lakes FL
Can you access the dowels through the acces cover on the bottom of the bellhousing?
I just swapped my clutch last week and I can feel the vibration at idle. Not horrible, but a little worse than it was stock. I am hoping I can press out the weights and see if it helps.
So can it be done without pulling the driveline again?
Thanks!
I just swapped my clutch last week and I can feel the vibration at idle. Not horrible, but a little worse than it was stock. I am hoping I can press out the weights and see if it helps.
So can it be done without pulling the driveline again?
Thanks!
Burning Brakes
Joined: Aug 2000
Posts: 889
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From: DFW tx
I just had my LUK pulled out due to vibration issues. It was 16 grams off. They are supposed to be balanced within 2 grams from the factory, I guess they have poor quality control.
The assembly was rebalanced and the vibrations are down, however they are not completely gone.
I am at the point where I am about to put a new engine in that is zero balanced so my vibration issues will be gone for good.
The assembly was rebalanced and the vibrations are down, however they are not completely gone.
I am at the point where I am about to put a new engine in that is zero balanced so my vibration issues will be gone for good.
Thread Starter
Race Director
Joined: Dec 2002
Posts: 10,233
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From: Baltimore suburbs Maryland
Originally Posted by SideStep
Besides cutting the weights off, did you tranfer any press-in weights from your factory flywheel??? If so did you remove those (pres-ins) also when you cut the other weights off???
Although the flywheel still was rebalanced, with 3 drill holes in the rear so this tells me something from the LUK assembly as still off.
Melting Slicks
Joined: Feb 2003
Posts: 2,966
Likes: 22
From: Frederick Maryland
St. Jude Donor '08-'09-'10-'11
Damn, this is all I needed to hear. My new motor is 0 balanced but there is a chance the LUK is not balanced? I just finished installing the motor yesterday! Uggggggggggg!!!!!!!!!!!!!!!!
Race Director
Joined: Mar 2004
Posts: 12,634
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From: IL, Chicago area.
St. Jude Donor '14-'15-'16
My McLeod w/ aluminum flywheel was zero balanced from the factory and I have 0 vibration. I guess I got lucky there. I have had (3) Spec clutches, (1) on my former WS6, (1) on my C5 which was replaced because it was so out of balance, and the replacement vibrated at about 1800 to 2000 RPM.
Last edited by PHPD7102; Jan 4, 2005 at 04:03 PM.
