Violent knocking/clunking

[blizz99]

My car is knocking/clunky very loud. I used a stethoscope and seems like it's coming from the clutch/flywheel area. The weird part is that when I press the clutch in, the noise goes away. I haven't had the time to take it apart yet but plan on doing it soon. Does anyone know what the issue can be? The last issue I had with the trans, during a wot run the flywheel ate the starter teeth. I don't know if it's pertinent info but thought I might add that info in. I had a couple friends mention the dreaded CW could be my issue, but I'm hoping that's not the issue.

 

[TrevorS]

My understanding of "CW" is that its symptoms are turn dependent. The question can be tested by checking the in/out crank shaft play. If the crank pulley exhibits inline motion, then there's a problem, otherwise there isn't.

Under what conditions are you hearing the knock/clunk problem?

 

[blizz99]

Idle and driving. There's nothing different when turning.

 

[rlacasse1]

How did the flywheel "eat" the started teeth during a WOT run? The gear on the starter should be nowhere near the flywheel when you are not "STARTING" the car. They wouldn't even be engaged.

Have you driven this car since it started making the noise? Why don't you just yank the trans out? It's only a couple hour job to get it out and back in.

It's more than likely not going to end up being crankwalk.

 

[WES_393]

Sounds like something clutch related to me. Possibly a bad throw out bearing or a missing bolt. Either way, its time to pull the trans. I highly doubt its crank walk.

You also might want to check your production date. Its possible you have a 6-bolt engine which almost never walks. But the 7-bolt walking is also rare so regardless I still doubt CW.

 

[blizz99]

How did the flywheel "eat" the started teeth during a WOT run? The gear on the starter should be nowhere near the flywheel when you are not "STARTING" the car. They wouldn't even be engaged.

Have you driven this car since it started making the noise? Why don't you just yank the trans out? It's only a couple hour job to get it out and back in.

It's more than likely not going to end up being crankwalk.

I dont know how/why it happened but it did. I haven't driven the car since the noise though.

Sounds like something clutch related to me. Possibly a bad throw out bearing or a missing bolt. Either way, its time to pull the trans. I highly doubt its crank walk.

You also might want to check your production date. Its possible you have a 6-bolt engine which almost never walks. But the 7-bolt walking is also rare so regardless I still doubt CW.

I'm thinking it's clutch related as well. I wanted to see if anyone has had the same thing happened and why. Once I have time I'll be pulling the trans to see what it is and try to figure out why it happened. FYI, the motor is a 7 bolt. I highly doubt it's CW too.

 

[TrevorS]

The last issue I had with the trans, during a wot run the flywheel ate the starter teeth. I don't know if it's pertinent info but thought I might add that info in. I had a couple friends mention the dreaded CW could be my issue, but I'm hoping that's not the issue.

It would take significant "CW" before the starter gear would accidentally engage the flywheel. Since it doesn't appear you have a "CW" problem, I'd be wondering about your starter, perhaps it isn't retracting from engagement properly !

 

[boosted99_420]

I had a small rattle before and it would disappear when clutch was engaged and ended up being a loose flywheel bolt. Maybe you just had the misfortune of having one back completely out or have multiple loose bolts and they have the flywheel loose and its the clunking sound you are hearing and as for CW idk why everyone jumps to that on 7 bolts I've see 6 bolts, 2jz, ls3, 302ci, b16s and all cranked walked its extremely rare for 7 bolts also.

 

[blizz99]

I've already replaced the starter with a new one and it's been good since. I'll be taking the trans off tomorrow to see what the issue is. I'll keep everyone posted with my findings.

 

[deviousgst]

I had same problem couole years ago. Ended up being my input shaft was messed up. Ended up buying another transmission ..
Heres my thread
http://www.dsmtuners.com/forums/drivetrain-tech/377419-transmission-sounds-like-rodknock-o.html

 

[blizz99]

Wow, that's really discouraging.

 

[turboglenn]

Mine did that, the flywheel had come loose, sounded like the loudest worst sound an engine/trans could ever make.. couldn't tell from inspection cover either, pulled trans and checked the bolts and found it.

 

[blizz99]

That's a lot better than the input shaft! I hope it'll be an easy fix like that. We'll see later today.

Just took everything out today. ALL of the flywheel bolts backed out! They didn't come out completely but they all were very loose. Gotta love simple, free fixes! Already put the clutch and flywheel on, with thread locker.