Hipmvmt

I put a new clutch and lightweight flywheel in my car about a month ago.
On the test drive I noticed a constant rattle while decelerating in gear. I parked the car and looked into the throw out bearing and the fork. Everything is seated and in place.
I also checked everything obvious, there are no b loose bolts, everything is torqed down.
I even called a shop, but I was told lightweight flywheels are just noisy.

Has anyone had a issue like this?

bmxhotsauce

iTrader: (3)

light flywheels has nothing to do with noise. sorry man

Hipmvmt

Thank you, I'm just trying to figure out where this noise/rattle is coming from. It's getting very frustrating.

pho_shizzle

iTrader: (17)

That is incorrect.

From the description you are providing....

Because a light weight fly wheel has a lighter overall total weight, it will have a difference in high rotational inertia and low rotational inertia. (correct me if I used the incorrect physics terminology)

In short, basically it is lighter so it will take less force to spin (hence your engine will rev quicker) and it will also slow down in rotations a lot quicker than the old flywheel in accordance to your engines crank. When rpms are dropping, the flywheel's rpm will drop down a lot quicker than what the engine is used to and you will hear some conflicting noises due to the difference in weight.

I have a light weight fly wheel and usually keep all revs consistently above 2000rpm or I will start hearing rotational noises from the fly wheel. If you have a light weight flywheel, your driving style will have to adapt and change along with it. So keep the rpms either higher, or always have a smooth transition through all gears and applying adequate power (gas) to keep the rotational mass on the fly wheel settled.

Stephen G

uhm i disagree with bmx... I had a stage one exedy clutch and light weight flywheel put in. I was told it was to be expected. It's not loud or anything but you have a little bit of noise. Mine was installed at Speed element and I was told that was to be expected. I think most of the people that had this done agreed about having some to little noise from the flywheel if you look it up in the forums. Although, you never know. You might want to have a professional look at it if your not sure.

OneManArmy

iTrader: (7)

Then you've clearly never had a light weight flywheel. Sorry but this dude is wrong.



I've had one in every manual trans vehicle I've owned... several different brands with several different clutches... THEY ALL MAKE NOISE.

There is a huge increase in drive train noise when you add a lwflywheel.

They make noise under decel and at lower RPM's. It's 100% completely normal. Don't stress on it. I'm happy to let you drive my car if you want. I guarantee you it sounds exactly the same way and I've got over 100k miles on this one at the moment with another one sitting in my garage ready to go. Same flywheels, same clutch.

The shop was telling you the truth. You'll get used to it.

bmxhotsauce

iTrader: (3)

i have had many light weight fly wheels and have a little noise now due to my exedy twin disc. i sounds more or a throw out bearing.. but bashing someone for a personal experience is horrible on your guy's part. i have had a lot of clutch and fly wheels in my day and have never had an issue with noise at all until i went to my twin disc on my fully built motor.

bmxhotsauce

iTrader: (3)

Rattling noise after clutch install, driving me INSANE.

bmxhotsauce

iTrader: (3)

does it sound like this?

02RS25

iTrader: (9)

i DOUBT its this, but have you checked your heat shields? mine would rattle at a specific RPM, especially when decel. just throwing some ideas out there. dont hurt to give them a wiggle

Hipmvmt

It doesn't sound like that. It really seems like a exhaust shield rattle, but only on decel in gear. If it's not going to break and doesn't sound like symptoms of something major then it won't bother me. I'll double check the heat shielding and definitely find out if that's it when I eventually get my exhaust. If that's not it maybe it exedys clutch disc springs.

ddavis

iTrader: (4)

Do you hear it when you push in the clutch all the way?
Do you hear it when you are braking?
Do you feel a vibration when it makes the noise?
Does it happen in every gear?

Could be alot of things since there's alot you mess with when uninstalling a transmission on these cars. If you dont feel like its the flywheel I would start by lifting the car up on some wheel cribs/ramps so the weight is loaded and start checking how much clearance you have around the drivetrain & exhaust parts. Things can get shifted when uninstalling a trans and they dont always go back up the exact same way they came off.

OneManArmy

iTrader: (7)

Then don't make a definitive closed statement that's wrong.

The problem with forums is this... when you write something and you sound like you know what you're talking about... people listen. Not just the guy you're talking to but everyone that searches "clutch noise" from now until eternity.

In this case you are wrong. Could it be a throw out bearing. Sure. But considering when the noise started... immediately after the install. Considering the set up and the description and what the shop said and and and and.... I really don't think it's the throw out bearing.

I personally drive the same car he does. I personally have pretty much the same set up he has. The noise he's describing is EXACTLY what mine does.

Same reason I was able to walk up to someone I never met and say... hey... that a perrin exhaust on your car. Does it do this. Yep... here's how you fix it. Experience with that exact set up and issue.

With that drive train and that set up it's normal. Just like the installer said.

PhoShizzle gave you a nicely written response that was more directed at the issue and less at you. Get mad at me, not him. Same with Stephan G.

Both helpful responses. I'm just an *******. Doesn't mean I was wrong.

wombatsauce

iTrader: (7)

Yup, I had an annoying decel rattle on my old 2.5RS after a lightweight flywheel and clutch install.

pho_shizzle's comments about keeping the revs up are very useful. It's true, and it's just something to get used to. Once you get the engagement point down, being able to power into a take-off is a pretty nice feeling.

On my current car, my latest rattles have been (all after a trans/clutch install):

1. Turbo heat shield
2. Bad U-joint bearing on driveshaft
3. $%&#ing change in my ash-tray

DarkJuic3b0x

iTrader: (3)

I've been having rattling issues lately too. I've been thinking it might have been my exhaust piping, but I don't know. It sounds like it's originating from the downpipe area.

What other heat shields, besides the turbo heat shield, are there?