Re: Return of the Rattling Spider Thread...

[Simon Favre <simon@domain.elided>]

The driveshaft pilot bushing is a suspect, as the noise went away after
grabbing the driveshaft. I would tend to think the pilot bushing would
make more of a clunking noise, not a tinny sheel metal noise. The 
driveshaft intermediate bearing could still do that, IMO. If the grease
is gone, the bearing retainer and rollers could be rattling, The support
for the bearing could be rattling against the driveshaft if the rubber is 
shot, so do look at that piece. Drop the bearing support and spin the 
bearing by hand. Sometimes, if you run over a rock, the bearing support
can be bent, too.

My "usual suspect" for a buzzing noise at 3000 RPM is the front resonator,
but you've already eliminated that one.

Hal Taylor wrote:
> 
> Simon,
> 
> Thanks for the response.
> 
> You're talking about that bracket with the two rubber bushings (grommets?)
> in it, right?  Yeah, that checks out ok.
> 
> Rubber bushings around the driveshaft intermediate bushings have not yet
> been checked.
> 
> The quality of this noise (thin and buzzy) suggests to me that it's
> something relatively light (?).  The exhaust bracket would have seemed
> right, but I don't think it's that.
> 
> Brian Shorey (who seems pretty savy, in general) has suggested that the
> pilot bushing in the driveshaft, which mates with the transmission's output
> shaft, could be the culprit.  I seem to get the noise equally whether the
> transmission is in neutral or driving the wheels, however; I'm not sure if
> that would be consistent with a  pilot bushing issue or not.
> 
> Feedback (anybody)?
> 
> Thanks again.
> 
> Hal Taylor
> '86 spider veloce "Strega" (like Marie Callas with laryngitis)
> 
> Simon Favre wrote:
> 
> > Have you thoroughly checked out the exhaust support bracket that bolts
> > to the tranny? This bracket has 2 pieces, one bolted to the tranny, and
> > one that attaches to the first piece with bolts through rubber bushings.
> > If either bracket is bent, or if the rubber bushings are shot, it can
> > rattle against the tranny support crossmember, making quite a racket.
> >
> > As the noise went away when they grabbed the driveshaft, this might be
> > a suspect. Something else to check would be the rubber around the
> > driveshaft intermediate bearing. Again, if the rubber is shot, you can
> > get a metal to metal rattle. There's nothing inside the gearbox that
> > should be able to rattle like this.
> >
> > Hal Taylor wrote:
> >
> > >Well, mine has had a nasty buzz at around 3000 rpm, since I've owned it.
> > >I originally thought it was exhaust and, piece by piece, I replaced the
> > >entire exhaust system, to no avail.

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