Clutch/ flywheel rattling? Experts please chime in.
04-13-2006, 02:56 AM
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Clutch/ flywheel rattling? Experts please chime in. I had to reinstall my Textralia OZ700 a couple months ago (the pressure plate bolts backed off from the shop using anti-seize on the threads 
)
Anyhow, reinstalled the pressure plate bolts w/ ARP ones and used red lock-tite on them. Torqued to 55ft/lbs. On the flywheel I used ARP bolts too. The ARP directions said to coat with moly-lube or 30wt engine oil only. I was going to use red lock-tite till I read that. Ended out using 30wt oil and torqued them to 75ft/lbs. I also added a McCloud adjustable master cylinder. Accidently sucked a little air into the resevoir when bleeding it....but all seemed well at the time. Put in a new slave too.
The car was smooth as silk after the re-install. Now, two months later the car seems rougher. Lots of engine vibrations at idle. It drives fine, save that sometimes I have full hydraulics on the clutch and other times a couple inches of free play (thinking that's the air in the Master cylinder?)
But....and this is what concerns me. If I turn the car off with the clutch pedal depressed to the floor, no rattles, etc. If I turn the car off with the clutch pedal NOT depressed and the car in NEUTRAL....I hear a rattle from the trans area for a second as the engine stops. I also have a lot of vibration through the stick and shift **** when the car is idling.
MY car has a cam and turbo....but the vibes seem pretty excessive. The car drives smooth and doesn't seem to stutter, but the whole engine looks like its shaking pretty good on the mounts.
Is is common (or possible) the flywheel bolts are backing out? I asked this Q a month ago and the symptoms I was told to look for didn't point in that direction. I was told to rev the car into the upper RPM band with the trans in neutral and see if I could feel vibration. No, seems smooth. It's the idle. The engine is running smooth, but again, there's a lot of vibration.
Sorry for such a long post, but I'm hoping someone can help. I'd hate to re-pull the trans for nothing more than paranoia, but I don't want to screw the engine up either.
)Anyhow, reinstalled the pressure plate bolts w/ ARP ones and used red lock-tite on them. Torqued to 55ft/lbs. On the flywheel I used ARP bolts too. The ARP directions said to coat with moly-lube or 30wt engine oil only. I was going to use red lock-tite till I read that. Ended out using 30wt oil and torqued them to 75ft/lbs. I also added a McCloud adjustable master cylinder. Accidently sucked a little air into the resevoir when bleeding it....but all seemed well at the time. Put in a new slave too.
The car was smooth as silk after the re-install. Now, two months later the car seems rougher. Lots of engine vibrations at idle. It drives fine, save that sometimes I have full hydraulics on the clutch and other times a couple inches of free play (thinking that's the air in the Master cylinder?)
But....and this is what concerns me. If I turn the car off with the clutch pedal depressed to the floor, no rattles, etc. If I turn the car off with the clutch pedal NOT depressed and the car in NEUTRAL....I hear a rattle from the trans area for a second as the engine stops. I also have a lot of vibration through the stick and shift **** when the car is idling.
MY car has a cam and turbo....but the vibes seem pretty excessive. The car drives smooth and doesn't seem to stutter, but the whole engine looks like its shaking pretty good on the mounts.
Is is common (or possible) the flywheel bolts are backing out? I asked this Q a month ago and the symptoms I was told to look for didn't point in that direction. I was told to rev the car into the upper RPM band with the trans in neutral and see if I could feel vibration. No, seems smooth. It's the idle. The engine is running smooth, but again, there's a lot of vibration.
Sorry for such a long post, but I'm hoping someone can help. I'd hate to re-pull the trans for nothing more than paranoia, but I don't want to screw the engine up either.
04-13-2006, 07:31 AM
#2
Regarding the rattling - In both my T/A, and my '03 Blazer with a 5 speed (bone stock) if I turn the car off with the clutch engaged, they both will rattle as the motor stops turning (and won't do it if the clutch is disengaged, like you said). In fact I think the Blazer does it worse. And similarly, if I leave both cars in neutral idling with the clutch engaged, I can usually hear a steady rattle from either, though with the loud exhaust on the T/A, its harder.
Basically IMHO the rattle is more from the transmission. In fact when I dropped the M6, I spun the input shaft by hand, and I could hear a rattle from the trans. I think it is just the sound of the trans gearsets spinning freely with no load. And the rattle is likely exacerbated by the unsteady harmonics of the engine when it is being shut off.
So I wouldn't worry too much about it. If it was a pressure plate problem, it should still rattle with the clutch disengaged - remember the pressure plate is fixed to the flywheel. So if it was loose and rattling, it would do so whenever the flywheel was spinning, regardless of clutch engagement.
The motor vibration I think is probably something all together different. With the kind of power your making, it might not be a bad idea to get some poly motor mounts, and that will keep the engine from rocking so much. The stock ones get torn up pretty quickly when you beat on them, especially with more power. I just put in poly mounts this winter, and they really work well.
Basically IMHO the rattle is more from the transmission. In fact when I dropped the M6, I spun the input shaft by hand, and I could hear a rattle from the trans. I think it is just the sound of the trans gearsets spinning freely with no load. And the rattle is likely exacerbated by the unsteady harmonics of the engine when it is being shut off.
So I wouldn't worry too much about it. If it was a pressure plate problem, it should still rattle with the clutch disengaged - remember the pressure plate is fixed to the flywheel. So if it was loose and rattling, it would do so whenever the flywheel was spinning, regardless of clutch engagement.
The motor vibration I think is probably something all together different. With the kind of power your making, it might not be a bad idea to get some poly motor mounts, and that will keep the engine from rocking so much. The stock ones get torn up pretty quickly when you beat on them, especially with more power. I just put in poly mounts this winter, and they really work well.
04-14-2006, 03:20 AM
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Thanks for the input guys. 
I ordered a set of poly motor mounts today. This is the 2nd time I've heard this might be my problem. (First time was from a Honda mechanic doing my annual inspection. 
) Tomorrow I'm also pulling my master cylinder to bench bleed again and get ALL the air out. I'm hooking it to an old slave and running a line from the slave bleed back to the master cylinder cap (tapped with a fitting) to get all the air out by creating a closed bleed system.
Again, appreciate the input.
I ordered a set of poly motor mounts today. This is the 2nd time I've heard this might be my problem. (First time was from a Honda mechanic doing my annual inspection. ) Tomorrow I'm also pulling my master cylinder to bench bleed again and get ALL the air out. I'm hooking it to an old slave and running a line from the slave bleed back to the master cylinder cap (tapped with a fitting) to get all the air out by creating a closed bleed system.Again, appreciate the input.
04-29-2006, 05:02 PM
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did the poly motor mounts fix your problem?
Im having some rattling with my tex clutch its only been in for 2 weeks. Ive got 150 miles on it. Im taking it back to the shop i had it installed at to get looked at.
Im having some rattling with my tex clutch its only been in for 2 weeks. Ive got 150 miles on it. Im taking it back to the shop i had it installed at to get looked at.
