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  • Stargazer

    April 28, 2009 5:56 p.m. Stargazer HalfDork

    My miata just recently starting making this noise. It's present at idle and sounds like a general grumbling sound and goes away when I push the clutch in. In 1st or 2nd gear at about 2k rpm, it's much louder and sounds like a stick in fan blades. Since it comes and goes with the clutch, I think it's somehow transmission related. Quick history on the car: '95 w/ approx. 235k on chassis, 170k on trans., 200k on torsen diff, 35k on speed longblock. It shifts fine, and everything feels fine aside from the noise. Ideas? Thanks!

  • GregTivo

    April 28, 2009 5:59 p.m. GregTivo Reader

    your throwout bearing's shot, you need to either replace the clutch or endure the noise until the clutch stops functioning and then replace the clutch.

  • Stargazer

    April 28, 2009 6:01 p.m. Stargazer HalfDork

    Forgot to mention - it's an ACT stage 1 clutch with 35k miles. Is it normal to die this soon?

  • GregTivo

    April 28, 2009 6:02 p.m. GregTivo Reader

    depends on if the throwout bearing was replaced with the last clutch. You could pull the transmission and replace the throwout bearing without touching the clutch itself, but you're still pulling the transmission. shrug

  • Tyler H

    April 28, 2009 6:23 p.m. Tyler H Dork

    The throwout bearings with aftermarket clutch kits are generally crap. I usually buy a new OEM bearing for a clutch job.

  • Stargazer

    April 28, 2009 6:49 p.m. Stargazer HalfDork

    How many hours to do a clutch job for a) DIYer with decent wrench skills and regular tools, b) mechanic ?

  • Stargazer

    April 29, 2009 8:39 a.m. Stargazer HalfDork

    Wouldn't a bad TO bearing make noise when the clutch is disengaged (pedal pressed)?

  • GregTivo

    April 29, 2009 10:42 a.m. GregTivo Reader

    Stargazer wrote:

    Wouldn't a bad TO bearing make noise when the clutch is disengaged (pedal pressed)?

    No, the throwout bearing is loaded by the transmission while the clutch is engaged and when the clutch is disengaged, the transmission load is gone. The pilot bearing on the flywheel is the opposite. While the clutch is pressed again the flywheel, the load on the pilot bearing is the least whereas when the clutch is disengaged from the flywheel, the pilot bearings load is greatest because now the weight is no longer supported by the transmission shaft.

  • GregTivo

    April 29, 2009 10:53 a.m. GregTivo Reader

    Stargazer wrote:

    How many hours to do a clutch job for a) DIYer with decent wrench skills and regular tools, b) mechanic ?

    The hardest part is the removal and reinstallation of the transmission and bellhousing. The PPF needs to be either removed or shifted out of the way and a section of the exhuast needs to be removed also. The actual removal and replacement of the clutch is fairly simple. A press is recommended to remove and reinstall the pilot bearing, but can be done with appropriate hand tools (such as a hub puller) An experienced mechanic may take 4 hours to do the job. A novice with the right tools (pnuematic operated and socket extensions) working in a typical garage, probably about 12.

    Its not the easiest job, but it is very doable by a DIYer.

 
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