928 CLUTCHES
06-19-2001, 01:41 AM
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928 CLUTCHES
Do you guys burn out clutches with all the low end torque.
I have heard that that is part of the reason 70 percent of the 928s bought in a certain time period were autos (also the fact that its a lux car and a cruiser).
But seriously, do you burn out clutches easily. Or is it just a myth. I am afraid of this. I have a 931 and am done with it but looking for 928.
I have heard that that is part of the reason 70 percent of the 928s bought in a certain time period were autos (also the fact that its a lux car and a cruiser).
But seriously, do you burn out clutches easily. Or is it just a myth. I am afraid of this. I have a 931 and am done with it but looking for 928.
06-19-2001, 03:18 AM
#2
USMarine
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Not a lot of experience burning out the dual disc pre-87 clutch. However, I have had one in the 85 and it took a extreme dump at about 6500 rpm.
06-19-2001, 08:36 AM
#3
Burning Brakes
A 928 clutch can last 150k miles or it can be used up in 50k miles, it mostly depends on the driver.
If you can be gentle on the clutch during up-shifts AND down-shifts, then it should last a very long time. YMMV.
If you can be gentle on the clutch during up-shifts AND down-shifts, then it should last a very long time. YMMV.
06-19-2001, 02:28 PM
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That is not nearly as bad as I thought...I hate it when people spread rumors, I swear everyone with Porsches is out to "get" the other guy with another model number, 911s won't believe a 924 turbo "S" in 1980 had better G force in lateral acceleration than the 911 SC in mid 80s, and boxters and 911s don't know 928s can eat them alive. And then there are the 928 owners who say that the weight of the 928 doesn't affect its handling... kmmmph
[ 06-19-2001: Message edited by: Lars ]
[ 06-19-2001: Message edited by: Lars ]
06-19-2001, 02:42 PM
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Lars,
According to Devek, the dual disc clutch is one of the best production clutch set ups made. The real problem was in the adjustments, most repair shops did not know how to properly adjust the clutch. The result premature burn up. However, Devek provides a great tech tip for the adjustment. I can testify to it's accuracy. My '84 Euro S, 5spd leaves pretty hard, lots of surface area on the dual discs.
Good luck in your shark hunt!
According to Devek, the dual disc clutch is one of the best production clutch set ups made. The real problem was in the adjustments, most repair shops did not know how to properly adjust the clutch. The result premature burn up. However, Devek provides a great tech tip for the adjustment. I can testify to it's accuracy. My '84 Euro S, 5spd leaves pretty hard, lots of surface area on the dual discs.
Good luck in your shark hunt!
06-19-2001, 06:12 PM
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ok so they didn't know how to adjust them...how? the clutch ride height, or something more complicated like angle ?
Like lets say i do a clutch on a 928 cuz it needs one...whatdoya gotta do to do it right, whats teh big mistake the guys made, one clutch wore out more than the other since its dual?
Like lets say i do a clutch on a 928 cuz it needs one...whatdoya gotta do to do it right, whats teh big mistake the guys made, one clutch wore out more than the other since its dual?
06-19-2001, 08:11 PM
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Lars,
Here is what Devek says about the adjustment.
They were also very helpful over the phone when the job was being done.
Adjusting the 928 double disc clutch center ring: The 928 double disc clutch is superior to any other production car clutch assembly. It is small in diameter, has a large surface area, low angular momentum and is easy to modulate. However, it does have one fault. Porsche discontinued the clutch at the end of 1986 because of continuing problems with having the clutch properly serviced in the field. If the center ring is out of position, the clutch, even in the fully disengaged position, will experience "drag". This drag will cause a creep when the car is standing still, in gear and idling. The clutch drag will also cause difficult shifting and grinding in reverse gear. The other aspect of the service problem is that improper lubrication of the clutch assembly and central shaft causes poor quality engagement and early failure of parts. The Fix: To properly adjust the center ring, remove the clutch cover and disengage the clutch by using a bar against the release bearing arm. In the disengaged position, the center ring should be equidistant from the flywheel and the pressure plate. If the center ring is out of position, reposition it by moving the adjusting forks of the center ring with a screwdriver. Rotate the engine by hand to gain access to each of the three adjusting forks. Disregard the dimensions given in the 928 factory repair manual! Lubricate all of the pivot points of the pressure plate diaphragm spring with dry molybdenum disulfide spray (such as Zep product #0073). Lubricate the central shaft and release bearing guide sleeve with moly paste. This procedure will assure easy modulation of, and long service life for, the double disc clutch assembly.
I hope this helps.
Here is what Devek says about the adjustment.
They were also very helpful over the phone when the job was being done.
Adjusting the 928 double disc clutch center ring: The 928 double disc clutch is superior to any other production car clutch assembly. It is small in diameter, has a large surface area, low angular momentum and is easy to modulate. However, it does have one fault. Porsche discontinued the clutch at the end of 1986 because of continuing problems with having the clutch properly serviced in the field. If the center ring is out of position, the clutch, even in the fully disengaged position, will experience "drag". This drag will cause a creep when the car is standing still, in gear and idling. The clutch drag will also cause difficult shifting and grinding in reverse gear. The other aspect of the service problem is that improper lubrication of the clutch assembly and central shaft causes poor quality engagement and early failure of parts. The Fix: To properly adjust the center ring, remove the clutch cover and disengage the clutch by using a bar against the release bearing arm. In the disengaged position, the center ring should be equidistant from the flywheel and the pressure plate. If the center ring is out of position, reposition it by moving the adjusting forks of the center ring with a screwdriver. Rotate the engine by hand to gain access to each of the three adjusting forks. Disregard the dimensions given in the 928 factory repair manual! Lubricate all of the pivot points of the pressure plate diaphragm spring with dry molybdenum disulfide spray (such as Zep product #0073). Lubricate the central shaft and release bearing guide sleeve with moly paste. This procedure will assure easy modulation of, and long service life for, the double disc clutch assembly.
I hope this helps.
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06-20-2001, 12:47 AM
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wow i have never had someone spend so much time on me, i really like these 928 guys (other than the drunk ones, but they also seem nice), its not just the cars, its the people 
You know what...there was also something similar to this with other porsches, but not because it was out of adjustment, but rather because of the clutch disc design. The little slots in the clutch help dislodge it, if it is a smooth clutch like sachs makes its bad for a vacuum holding it
You know what...there was also something similar to this with other porsches, but not because it was out of adjustment, but rather because of the clutch disc design. The little slots in the clutch help dislodge it, if it is a smooth clutch like sachs makes its bad for a vacuum holding it
