Strange Noise
Thread Starter
Track Day
Joined: Nov 2007
Posts: 17
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From: Scotland, UK
Strange Noise
Guys, UMW rebuilt turbo's and lightweight clutch kit, now have a few miles on them and the good news is I'm well happy. When we stripped the old turbo's off one was fine the other was clearly oast its best with lots of oil evident in the pipes...not good. Driving the car now I find its much smoother on boost and so far no issues in moving to the lightweight clutch with the car feeling a bit more eager (and I can't believe how heavy the standard assembly is)...although Mrs O' hasn't driven it yet, so that will give me the final verdict.
So top job by Kevin at UMW, my tech seems to have done his usual good job at a fair cost and gave the rest of the car a clean bill of health, while it was there.
However, something has changed and is clearly following the recent work... there is a metallic resonance like a rattle at just under 3k revs when I dip the clutch and bizzarely when cornering to the right, it seems to be form the back right corner of the cabin in the engine compartment. We've checked all the easy stuff and its booked in next week for investigations, but wondered in anyone else had encountered such an issue...a heatshield or something like that?
So top job by Kevin at UMW, my tech seems to have done his usual good job at a fair cost and gave the rest of the car a clean bill of health, while it was there.
However, something has changed and is clearly following the recent work... there is a metallic resonance like a rattle at just under 3k revs when I dip the clutch and bizzarely when cornering to the right, it seems to be form the back right corner of the cabin in the engine compartment. We've checked all the easy stuff and its booked in next week for investigations, but wondered in anyone else had encountered such an issue...a heatshield or something like that?
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Joined: Jun 2001
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From: Gulf of America-Pacific NW
It could be your heat shield rubbing on the Andial sump line. The sound would be more of a "buzz"
Please realize that under 2200 RPM's the clutch disk will have a rattle sound if you are lugging the engine. Once you boot the throttle, the noise will subside.
Please realize that under 2200 RPM's the clutch disk will have a rattle sound if you are lugging the engine. Once you boot the throttle, the noise will subside.
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From: Austin,TX
Single mass flywheel noise
Typically you can expect some more noise on a 993tt when moving from a dual mass to single mass flywheel. The dual mass flywheel is designed for enhanced vibration dampening and reduction of transmission gear rattle. It tends to be heavier so it slows the run up of the engine slightly. I replaced the dual mass flywheel on my 993tt a while ago. I have encoutered some of the same noises that you describe but expected them since decreased dampening can lead to resonance at certain frequencies. The feel of the new clutch more than compensates for this in my view.
Racer
Joined: Nov 2006
Posts: 259
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From: Brisbane, Australia
I agree with you about the noise from the LWFW/Clutch however I'm not sure the symptom fits. The expected noise is generally heard at low RPM when especially under load at low RPM with the clutch out, such as slowly driving up an incline in second at 1000-1500 RPM (my steep driveway is a good example). It it not influenced by cornering and further Macka's symptom occurs when he "dipps" the clutch, by thich I think he means clutch in momentarily. I'd be looking elsewhere per Kevin's suggestion.
Drifting
Joined: May 2004
Posts: 2,193
Likes: 18
From: New Zealand
Malcolm,
The day I bought my car I was going up my steep driveway and heard the same thing. Initially I crapped myself, but then I rang a specialist. He told me it was the LWF set up, and like yours, it only happens at low revs, and under load.
It's all part of the set up. I like it now, especially knowing what it is.
The day I bought my car I was going up my steep driveway and heard the same thing. Initially I crapped myself, but then I rang a specialist. He told me it was the LWF set up, and like yours, it only happens at low revs, and under load.
It's all part of the set up. I like it now, especially knowing what it is.
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Thread Starter
Track Day
Joined: Nov 2007
Posts: 17
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From: Scotland, UK
Guys, thanks for all the advice and suggestions...I don't think its the clutch, my tech said that I could experience some more noise he called it chatter, but the symptom doesn't seem to fit.
I'll let you know the outcome..thanks again
I'll let you know the outcome..thanks again
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