Flywheel rattle
Thread Starter
Safety Car
Joined: Mar 2005
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From: Winnipeg Manitoba, Canada
Flywheel rattle
I started a thread a week or 2 ago about my buddies tranny rattling. It turns out its the flywheel. I was told it was the ball bearings (or somthing along those lines) that are worn and rattling at idle. Our mechanic friend said it might be possible to fix them. Anyone have a similair experience with somthing like this?
Last edited by jimmers; Jun 7, 2007 at 05:05 PM.
Drifting
Joined: Aug 2006
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From: Canandaigua New York
I started a thread a week or 2 ago about my buddies tranny rattling. It turns out its the flywheel. I was told it was the ball bearings (or somthing along those lines) that are worn and rattling at idle. Our mechanic friend said it might be possible to fix them. Anyone have a similair experience with somthing like this?
If it's a stick, it could be a worn out throw out bearing.
If it's an Automatic, then it sounds like it's cracked.
Either that, or the front pump is on it's way out.
Thread Starter
Safety Car
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From: Winnipeg Manitoba, Canada
Team Owner
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
If your mechanic friend thinks there are ball bearings in the flywheel, you need a new mechanic, friend.
This is part of the design of the 6-speed transmission, it's just plain noisy at idle on warm fluid. It is very often misdiagnosed as bad input shaft bearings, or a bad pilot bearing. Without hearing yours personally, I can't tell you for sure if your noise is normal, but it probably is.
Does he have the stock flywheel?
Is his vette pre-94 or not?
This is part of the design of the 6-speed transmission, it's just plain noisy at idle on warm fluid. It is very often misdiagnosed as bad input shaft bearings, or a bad pilot bearing. Without hearing yours personally, I can't tell you for sure if your noise is normal, but it probably is.
Does he have the stock flywheel?
Is his vette pre-94 or not?
Thread Starter
Safety Car
Joined: Mar 2005
Posts: 4,723
Likes: 11
From: Winnipeg Manitoba, Canada
If your mechanic friend thinks there are ball bearings in the flywheel, you need a new mechanic, friend.
This is part of the design of the 6-speed transmission, it's just plain noisy at idle on warm fluid. It is very often misdiagnosed as bad input shaft bearings, or a bad pilot bearing. Without hearing yours personally, I can't tell you for sure if your noise is normal, but it probably is.
Does he have the stock flywheel?
Is his vette pre-94 or not?
This is part of the design of the 6-speed transmission, it's just plain noisy at idle on warm fluid. It is very often misdiagnosed as bad input shaft bearings, or a bad pilot bearing. Without hearing yours personally, I can't tell you for sure if your noise is normal, but it probably is.
Does he have the stock flywheel?
Is his vette pre-94 or not?
Sorry for the lack of info, I keep telling him to join the forum but he never does.
Team Owner
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
The rattle will get louder as the fluid warms up and thins out, or if the fluid level is low.
It's also plausible that the flywheel is wearing out and making it louder. People don't seem to get much more than 100K out of their ZF6 flywheels. Maybe one of them will chime in and say if those are some of the symptoms.
It's also plausible that the flywheel is wearing out and making it louder. People don't seem to get much more than 100K out of their ZF6 flywheels. Maybe one of them will chime in and say if those are some of the symptoms.
Safety Car
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From: Toronto ontario
If you heard my tranny at 600 rpm you'd think you were at war. The stock dual mass flywheel dampens the engine pulses at idle so it stops the tranny from rattling. the rattling does no harm and is part of the zf-6 design. I sacrificed the quietness of a 45lb dual mass for a 7 lb alum flywheel.
SO if your tranny is rattling at idle, your dual mass may be on its way out.. OR your idle is a little rougher than it should be and the dual mass can only dampen so much.
SO if your tranny is rattling at idle, your dual mass may be on its way out.. OR your idle is a little rougher than it should be and the dual mass can only dampen so much.
Thread Starter
Safety Car
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From: Winnipeg Manitoba, Canada
If you heard my tranny at 600 rpm you'd think you were at war. The stock dual mass flywheel dampens the engine pulses at idle so it stops the tranny from rattling. the rattling does no harm and is part of the zf-6 design. I sacrificed the quietness of a 45lb dual mass for a 7 lb alum flywheel.
SO if your tranny is rattling at idle, your dual mass may be on its way out.. OR your idle is a little rougher than it should be and the dual mass can only dampen so much.
SO if your tranny is rattling at idle, your dual mass may be on its way out.. OR your idle is a little rougher than it should be and the dual mass can only dampen so much.
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Thread Starter
Safety Car
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From: Winnipeg Manitoba, Canada
I've been doing a fair bit of reading and the rattle is common it seems. I've read that it should only happen in neutral with the clutch let out, but with his car it happens all the time at idle no matter what gear your in or if the clutch is in or out. Being in gear with the clutch in or out at idle wouldnt affect the rattle, you are still at the same idle no matter what gear your in. Right?
I apologize for the questions, this is all new to me.
I apologize for the questions, this is all new to me.
Last edited by jimmers; Jun 7, 2007 at 08:42 PM.
Thread Starter
Safety Car
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From: Winnipeg Manitoba, Canada
I've been told that since its a dual mass flywheel, you can weld them together to elimate the rattle or possibly add ball bearings??? Anyone heard of anything like this before? I havent!!!
Last edited by jimmers; Jun 8, 2007 at 05:12 PM.
Race Director
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From: Indianapolis IN
, run dont walk from them.Add ball bearings?? Is this Candid Camera?
Thread Starter
Safety Car
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From: Winnipeg Manitoba, Canada
Those were my thoughts exactly. I've never heard of anything like that before. Three people actually said it might be possible, but I trust you guys before anyone else.
Race Director
Joined: Feb 1999
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From: Indianapolis IN
He could do a Single Mass , but it will be louder, the DM has a rubber elastomer between he drive portion and the engagement hub that helps to dampen the rattle.
There is a thread on the forum ongoing about the Design of the DMF, check it out
http://forums.corvetteforum.com/show....php?t=1720732
Last edited by LD85; Jun 8, 2007 at 06:13 PM.
Drifting
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Actually, his mechanic is pretty smart. The dual mass flywheel DOES have ball bearings in it. Check out this thread and picture! forums.corvetteforum.com/showthread.php?t=1720732
Thread Starter
Safety Car
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From: Winnipeg Manitoba, Canada
Independent of their suggestions your buddy should just buy a New DM flywheel and forget about it.
He could do a Single Mass , but it will be louder, the DM has a rubber elastomer between he drive portion and the engagement hub that helps to dampen the rattle.
There is a thread on the forum ongoing about the Design of the DMF, check it out
http://forums.corvetteforum.com/show....php?t=1720732
He could do a Single Mass , but it will be louder, the DM has a rubber elastomer between he drive portion and the engagement hub that helps to dampen the rattle.
There is a thread on the forum ongoing about the Design of the DMF, check it out
http://forums.corvetteforum.com/show....php?t=1720732
Thread Starter
Safety Car
Joined: Mar 2005
Posts: 4,723
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From: Winnipeg Manitoba, Canada
Actually, his mechanic is pretty smart. The dual mass flywheel DOES have ball bearings in it. Check out this thread and picture! forums.corvetteforum.com/showthread.php?t=1720732
So maybe the mechanic isnt a quack 
Maybe he's not explaining himself fully.
Last edited by jimmers; Jun 8, 2007 at 06:42 PM.
Le Mans Master
Joined: Jul 2001
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From: Santa Maria, CA
There is NO rubber elastomer in the DMFW.
Add ball bearings?
umm...no.
Weld the 2 masses together?
Will shock the driveline component into premature wear if not breakage(spindles). (the clutch disc has no sprung hub)
Add ball bearings?
umm...no.
Weld the 2 masses together?
Will shock the driveline component into premature wear if not breakage(spindles). (the clutch disc has no sprung hub)
Safety Car
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From: Toronto ontario
If the noise is happening clutch in our out.. something is wrong. My guess is the dual mass does need a replacement. Does it make noise when accelerating lightly ? Under acceleration the dual mass will move accordingly in the direction of motion and it should be quiet unless youre in too low of a gear and under load.
I use a single mass and it is loud at low rpms under load and at low idles BUT when i push the clutch in.. all goes silent. If you are getting a rattle all the time some thing could be touching the exhaust? check to see if anything in the driveline is loose?
I don't want to judge your mechanic.. but welding the dual mass together is the stupidest thing I have ever heard. WHy have a 45 lb tank flywheel welded to act like a single mass when you can buy a single mass for cheap and save 38 lbs ? A dual mass has stuff in it fuild or ball bearings or rubber etc that can deteriorate over time.
I use a single mass and it is loud at low rpms under load and at low idles BUT when i push the clutch in.. all goes silent. If you are getting a rattle all the time some thing could be touching the exhaust? check to see if anything in the driveline is loose?
I don't want to judge your mechanic.. but welding the dual mass together is the stupidest thing I have ever heard. WHy have a 45 lb tank flywheel welded to act like a single mass when you can buy a single mass for cheap and save 38 lbs ? A dual mass has stuff in it fuild or ball bearings or rubber etc that can deteriorate over time.
Race Director
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From: Indianapolis IN
OK, I stand corrected, then what is all the talk about coolant from a blanchard grinder eating the rubber? Didint someone post a pic of a disc they had torn apart that had rubber in it?
"A DMF is tuned by the manufacturer to match engine torque and horsepower curves, engine harmonics, and vehicle load dynamics, based on transmission gear ratios as well as overall rolling diameter of the rims and tires. It is constructed by splitting the standard single mass flywheel in half. The primary section bolts to the engine crankshaft and the second section is where the clutch assembly is installed. Contained within the two sections is a complex system of varying rate springs, axle and radial bearings, and lubrication. The two halves are rubber-sealed. The aforementioned series of components is referred to as the friction pack. The main purpose of the friction pack is to absorb vibration, allowing for smooth, comfortable shifting, low speed driveability, and reduced drivetrain noise"