About 100 miles from Parade, the GT started making a loud, but lowish frequency noise. It sounded like very loud road noise or a really bad wheel bearing.

We discovered that it was tied to RPM rather than running gear and pulled over at a gas station to check it out. Checking out the underside, it sounded like an exhaust leak. It had that "wap, wap" sound to it that you get from an exhaust leak. But I couldn't find anything unusual otherwise. No indications under the hood, nor was any of the noise originating from there.

The noise got louder with RPM. No change in sound w/ the clutch in or out.

We shut it down, made a head call, started it back up and the noise was gone. We got back on the road and no noise the rest of the drive. We had no issues prior to that, even in high 80s temps with the a/c running the whole time.

I know not much to go on, but if anyone has any ideas, I'm open.

Not much driving the next couple of days, as I'll be prepping for the Concours, but TSD rally on Tues and a drive to Indy Speedway on Wed, both of which I'll skip if required to get it home in one piece on Thurs. Unfortunately, it's a 750 mile trek.

Thanks.

 

George sorry to hear the news,
I would guess its probably the throwout bearing letting you know is on the way out,
since it spins all the time with the engine speed.

On the TOB you may be able to prolong its life ,
I would suggest that they die from lack of lubrication.

To change that remove the clutch pack,
get a very sharp drill bit, drill a very small hole into the shield of the TOB bearing,


take a Zerk fitting and a hypodermic needle and screw/ press them together so the ball end can now be fitted to the grease gun.

you now have a very handy way to inject grease into the small hole you just drilled,'
add grease till the grease comes out the edges of the seal.

wipe off the excess use parts cleaner, then a dab of silicone will seal it.

NOTE when fitting a new TOB it is also a good idea to add some grease as they all seem to be hit or miss as to the grease quantity .

 

Condition/age of the motor mounts? If or when the engine touches the crossmember, it'll set up a pretty decent hum. Acoustics can make it worse. will change with engine speed, and can go away on it's own if the pan is just barely touching.

 

Doc thats good idea ,George could check the oil pan to see how low it is,
SB flush with the cross member

 

Thx guys. Sorry for the delay. Swamped here with concours preps and hanging out with friends.

Motor mounts are of the solid variety. While they have settled a little over the last 5 years, they appear to be ok.

TOB is something I wouldn't have thought of. Altho, the clutch does chatter a little when disengaged, but quiets down when pushed in. Not sure if that's related. My G50 equipped 911 has always done that.

Didn't know it was always spinning, even with foot off clutch. That's not conducive to long life...

 

thats why I added the greasing instructions for the TOB
I hope you dont have any other issues,
good luck with the concourse,
you have a terrific car in great condition and an excellent color

 

Or just take the throwout bearing unit apart, and stick the bearing in your bearing greasing tool. No destructive drilling.





89 S4 throwout bearing apart








Greased nicely

 

Sorry, I can't be of much help here. Any other nice 928's there? Be sure to post lots of pics!

 

Thx for the input. Plan is to bag out of driving in the TSD Rally and Indy Speedway tour and save the car for the trip home. Will ride along with friends that have a Macan, so at least we'll still get to go.

Got 2nd in class... Not happy about that. Didn't spend all that time prepping to get 2nd place, but that's the way it goes, I guess.

 

Pano of the 60 4 60 and Historic display cars

 

Wolfgang across from Pete Stout

 

..

 

,,,

 

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