Clutch job wisdom Options

[JeffBowlsby]

So my clutch has just started to slip and it chatters sometimes on launch. I thought I would first adjust it to see if it helps, but may need a new clutch. I have done thsi job before with all the recommended felts washers, flywheel O-rings etc. I don't seem to be having any leakage, burning smells and I have receipts from when I bought the car saying it has a recent new flywheel.

I will do whatever is necessary once I am in there, but don't want to remove the flywheel or do anything not needed.

Assuming nothing is worn or broken (I will replace or resurface things if they are worn), does it make sense that I can get by with just replacing the clutch disk? Can I reuse the pressure plate, T/O bearing, T/O bearing guide clips?

Pelican recommends the 6-spring disk: "We recommend using the 911 clutch package in the 914, as it gives the clutch a better feel." I tried the 6-spring disk once and it was fine of course, but what is the problem with using the stock 4-spring disk (its $125 cheaper)? My car is a daily driver street-use only and with the stiffer disk I wonder if the stronger springs contribute to clutch-tube breakage problems. Help!

[jcd914]

You can of course reuse most anything if you really want to.

If the clutch is slipping and chattering you may have hot spots on the surface of the flywheel and pressure plate. When the hot spots develop the expanding metal actually creates a high spot on the surface of the flywheel or pressure plate contributing to the chatter that is common with a worn clutch. So even though your flywheel is new it may need to be resurfaced to get rid of the hot spots or other bad wear conditions. If the flywheel is in good condition and not leaking oil at the main seal then I would leave it in place but I would check the end play on the crank.

I believe I have only seen 1 pressure plate fail mechanically (spring broke) so if the contact surface is OK and the wear on the fingers (where the TO bearing presses) is minor you may be able to reuse it. You also want to check that all the fingers on the pressure plate line up even with each other. If the fingers are not even the diaphram spring is distored and the pressure plate will not engae or retract evening, one edge will contact before the other.

The springs in the clutch disc are there to absorb rotation pulses of the engine. They are under the most load as you start off and engage the clutch but they are also under load when accelerating and just cruising along since the engine is always pulsing. I suspect the primary reason to use the 911 6 spring disc is to spread the load over 6 springs instead of 4. Under heavy loads the springs will be compressed to the point of coil bind and in time they may fatigue and break.

I would replace all the plastic wear parts because that are cheap and made to wear. I would think twice before reusing the TO bearing or the pilot bearing. Bearings are hard to inspect and evaluate their condition and their failure could be more costly than not replacing them. The TO bearing take out the pressure plate, seizing and chewing up the PP fingers. The pilot bearing could take out the mainshaft, seizing and chewing up the end of the shaft. On a clutch job for a customer only rare occasions would any of the parts be optional.

Good Luck
Jim