Throwout bearing bent
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From: Austin/Cedar Park
Throwout bearing bent I was having a vibration and clunking noise at rpm in most gears that louder as you progress from 3rd to 6th.
So i pulled the transmission and the throwout bearing is whobbling, If i set the pressure plate on the ground and spin it, you can hear the sides touching in random locations. I think as a result the pilot bearing is worn too.
Iv only put 130 miles on the setup, its a competition stage 2 clutch and fidanza flywheel. Everything was torqued properly when I removed it.
What could cause this?
So i pulled the transmission and the throwout bearing is whobbling, If i set the pressure plate on the ground and spin it, you can hear the sides touching in random locations. I think as a result the pilot bearing is worn too.
Iv only put 130 miles on the setup, its a competition stage 2 clutch and fidanza flywheel. Everything was torqued properly when I removed it.
What could cause this?
Does it look visibly bent? It's supposed to float on the PP fingers so I am not sure the test you did regarding spinning it is the best way to deduct something is wrong. Do you have a pilot bearing or bushing? There really should be no load on the bearing. It just aides in keeping the shaft centered. Is the input shaft marked up in any way? Was this clutch used or new and did it just start doing it or has it done this since it was installed? What do the clutch and flywheel surfaces look like?
Also the TOB is self centering. When it doesn't have the input shaft running through it you can push and pull the center with attached washer from side to side and when you spin it it will wobble. This is normal.
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From: Austin/Cedar Park
Does it look visibly bent? It's supposed to float on the PP fingers so I am not sure the test you did regarding spinning it is the best way to deduct something is wrong. Do you have a pilot bearing or bushing? There really should be no load on the bearing. It just aides in keeping the shaft centered. Is the input shaft marked up in any way? Was this clutch used or new and did it just start doing it or has it done this since it was installed? What do the clutch and flywheel surfaces look like?
Yes it looks visibly bent, I set it down flat on a level surface and put a spin on, you could hear the sides touching in a uneven pattern. Sorry im not very good at describing it, I could take a video tomorrow. The input shaft looks fine.
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as noted the TO bearing is self centering and does "float" around the input shaft. If you spin it in your hand it will have a off center rotation to it, normal.
What is not normal is when the lip (part fork sits under) get folded/bent back. If this is your case you need a new TO bearing
like any bearing the bearing itself could be bad and if you feel it rubbing or scraping by just turning it in your hand it is bad.
These TO bearings are China junk and have failed before. Usually with the lip folding/tearing away
There is a square top one with a little more meat on the bones in terms of flange thickness. Tese were used on the LT4 Vettes
SPEC sells them IIRC for around $80, not cheap. There may be other sources for them
pic shows difference between the two TO bearings
What is not normal is when the lip (part fork sits under) get folded/bent back. If this is your case you need a new TO bearing
like any bearing the bearing itself could be bad and if you feel it rubbing or scraping by just turning it in your hand it is bad.
These TO bearings are China junk and have failed before. Usually with the lip folding/tearing away
There is a square top one with a little more meat on the bones in terms of flange thickness. Tese were used on the LT4 Vettes
SPEC sells them IIRC for around $80, not cheap. There may be other sources for them
pic shows difference between the two TO bearings
How are the bushings on the LCA's and trans mount? Both of those can cause clunking when there's sudden load on the drivetrain. If the input shaft has no markings then your pilot bearing/bushing is fine.
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From: Austin/Cedar Park
Please review this video.
https://www.youtube.com/watch?v=MkmPgO1oBBo
The motor and trans have new bushings, you could hear the noise on jackstands when I was doing a drive cycle.
https://www.youtube.com/watch?v=MkmPgO1oBBo
The motor and trans have new bushings, you could hear the noise on jackstands when I was doing a drive cycle.
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From: Kernersville, NC
Bearing looks fine to me too.
My flywheel looks worse, but I've got quite a few more miles on my setup. Interesting that is the "puck" side of the clutch disk shows the most heat on the surfaces.
Any indications the clutch is slipping?
Are you grinding gears when shifting?
Where/When are you feeling the vibrations?
Do the vibrations get worse as rpm increases?
Can you be more specific on the clunking noise?
Does the clutch pedal engage like stock(how high off the floor when it grabs/disengages)?
My flywheel looks worse, but I've got quite a few more miles on my setup. Interesting that is the "puck" side of the clutch disk shows the most heat on the surfaces.
Any indications the clutch is slipping?
Are you grinding gears when shifting?
Where/When are you feeling the vibrations?
Do the vibrations get worse as rpm increases?
Can you be more specific on the clunking noise?
Does the clutch pedal engage like stock(how high off the floor when it grabs/disengages)?
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Jay
from this side of the internet you clutch, TO bearing, PP, FW look fine. Can't "see" the inside part of pilot bearing but if the roller needles are not compromised and the tip of input shaft look fine all should be good to go regarding the clutch part
yeah it is weird TO bearing has that "off center" rotation deal but they are all that way
Just take some emery cloth if you want and clean up FW & disc surfaces or just put it all back in
if you have vibration or clunking I would look closer at tranny & motor mount...and possible grounding at some point as a result of engine/tranny movement
from this side of the internet you clutch, TO bearing, PP, FW look fine. Can't "see" the inside part of pilot bearing but if the roller needles are not compromised and the tip of input shaft look fine all should be good to go regarding the clutch part
yeah it is weird TO bearing has that "off center" rotation deal but they are all that way
Just take some emery cloth if you want and clean up FW & disc surfaces or just put it all back in
if you have vibration or clunking I would look closer at tranny & motor mount...and possible grounding at some point as a result of engine/tranny movement
