Odd transmision noise... any thoughts

[Zivic]

Finally got my 350z back on the road after a full motor rebuild.

put some 75 miles on it yesterday and at idle I hear a clicking/tapping noise from the trans. having the car up on the hoist it almost sounds like it is coming from the center of the trans.

It's definitely coming from the trans and not the engine. Car drives and shifts as it should. Nothing else noticeable except the noise at idle. upon start up, no noise, but after 30 - 60 seconds the noise starts up. mechanic thought maybe the clutch pedal needed adjusting as possibly the throwout bearing wasn't releasing all the way. I made adjustments both ways on that without it making the sound better or worse.

plan is to pull the trans to investigate. would like to know if anyone has insight into something to look at/adjust/fix prior to pulling the trans?

specs
-2004 350z
-ATS twin disc carbon clutch - about 10-12k miles on it. looked good upon install with new throwout bearing
-CD009 (newest revision) 6 spd transmission - this is a used trans with 60k miles on it. I installed last year and drove it for about 2-3k miles without issue. Oil level in trans is good

LINK to Vid

 

[boomerang]

Too much of a coincidence. It has something to do with the work that was done, not a problem within the trans IMO. What happens when you push and hold in the clutch? Is the noise still present?

With the clutch disengaged the input shaft should eventually stop spinning and there will be no noise if its within the trans. If it's still making noise, check for anything that would lead to a misalignment between the engine and the trans before pulling it and if you do pull it, check the flywheel mounting, the clutch mounting and the throwout bearing.

Is it the original flywheel? Had it been ground?

 

[Zivic]

Too much of a coincidence. It has something to do with the work that was done, not a problem within the trans IMO. What happens when you push and hold in the clutch? Is the noise still present?

With the clutch disengaged the input shaft should eventually stop spinning and there will be no noise if its within the trans. If it's still making noise, check for anything that would lead to a misalignment between the engine and the trans before pulling it and if you do pull it, check the flywheel mounting, the clutch mounting and the throwout bearing.

Is it the original flywheel? Had it been ground?

good input

When I had it the mechanics house, noise went away upon pushing the clutch. which is why we thought it had to due with clutch adjustment....

though when I had it at my shop, I pressed the clutch and it didn't affect the noise (still present). I should try this again though as you bring up a good point just to make sure.

brother and I installed the trans after mechanic put the clutch on. clutch is $2K+, trans is only $600 bucks 😉 anyways tans went in very easily. about as easy as I have ever put in.

the ATS clutch comes as a complete assembly with its own flywheel. nothing was machined, turned, refaced on the clutch assembly. simply unbolted and then bolted into place after the rebuild

 

[Bartman39]

brother and I installed the trans after mechanic put the clutch on.

I would say "Bingo"... Now who put the flywheel bolts in...? Do you think that one of them is loose and has backed out which also means it might be hitting the dampener springs...?

 

[NAC4EV]

Release bearing or input shaft bearing

 

[Zivic]

I would say "Bingo"... Now who put the flywheel bolts in...? Do you think that one of them is loose and has backed out which also means it might be hitting the dampener springs...?

mechanic put the flywheel on. I simply lifted the trans in place and bolted it up