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Rooy · Joined: 16 Jul 2005 Posts: 41 Location: Neenah, WI

Hi guys, I'm trying to track down a nasty vibration coming from the driveshaft in a '78 924. It has a 5 spd trans and driveshaft out of an '82. Believe it is the '016/9' type.

The vibration appeared right after a spirited driving session including a pull to 6k up a hill in 2nd. The vibration is only apparent at revs above 3k, regardless of gear or speed.

I've pinpointed it to the driveshaft itself. With the car at a stop, clutch engaged (pedal up), revving it above 3k produces the vibration. With clutch disengaged, there is no vibration. So it is only happening when the driveshaft is spinning.

I'd appreciate any help in diagnosing this. Thanks!

Andrew
Neenah, WI

Ozzie · Posted: Sat Jul 16, 2005 8:33 am Post subject:

Torque tube bearings?
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Joes924Racer · Posted: Sat Jul 16, 2005 9:55 am Post subject:

nope its the clamping sleeve nasty little piece located in the tranny its the the equivalent to a u-jount in a conventional driveshaft car...they break causeing a bad vibration. its no joy to get to iether.
http://www.924board.org/viewtopic.php?t=8575&highlight=shift+coupler
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
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endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

Yea, think Ozzie has it right. Mine does almost exactly the same thing and I know without a doubt my bearings are going.

Todd

Hmm, just saw Joes response and I have no idea what your talking about but it may be somethng.

Joes924Racer · Posted: Sat Jul 16, 2005 10:52 am Post subject:

its a shift coupler i called it a clamping sleeve lets see what the pet cd calls.
you know it connects the 2 drive shafts ends together to form one..
when my rear wheel bearings went they made alot of noise with the the
balls catching in there races it was terrible.
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Rooy · Joined: 16 Jul 2005 Posts: 41 Location: Neenah, WI

Joes924Racer · Posted: Sun Jul 17, 2005 3:17 pm Post subject:

yea happend to me right at 3200 rpm then went away alil under 4 grand
http://images.snapfish.com/34447%3A8723232%7Ffp3%3B%3Dot%3E2329%3D969%3D%3A49%3DXROQDF%3E2323972%3B7%3B4%3A6ot1lsi
heres a pic of where the clamping sleeve is located all you gotta do is
secure the rear end up and then attach a fllor jack to the tranny then loosen it all up including the axels being removed and pull it back after loosening on e end of the sleeve then after its loose on one end youll most likel;y have to rotate the motor a lil to get to the allen bolt on the other end of the claming sleeve then once both ends are loose you can pullthe tranny it back to get out the clamping sleeve this job will give you wonderous rewards and isnt that hard really. Good luck & check out the pic might help you a lil.

_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

leadfoot · Posted: Mon Jul 18, 2005 7:21 pm Post subject:

Hey Joe the link you supplied to your info on fixing the problem didn't include the pics anymore. If you still have them would you mind posting up a couple, I'd be interested in seeing one of the broken coupler.
thanks
Leadfoot.
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
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Rooy · Joined: 16 Jul 2005 Posts: 41 Location: Neenah, WI

Update: got under and looked at the clamping sleeve through the inspection hole. Looks fine. The welds are still intact. So, I guess it's time to look at the driveshaft bearings. Just need to get my normal daily driver fixed so I can take the 924 off the road for a while.

Vince Ponz · Joined: 02 Nov 2002 Posts: 3581 Location: Florida

Too bad you are so far away. I have a good torque tube in the garage.
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77.5 924 modified track car
79 931 Euro stock
88 924S SE
87 911 Targa stock