Can I Change My Own Clutch?

Having a new clutch installed on your Porsche 924, 944 or 924S can be an expensive endeavor.  It’s not that the parts are expensive – a Sachs clutch kit is only about $500.  However, the labor to install it can be a bit spendy.  The labor rate books call for something around 15-16 hours for an NA car, more for a turbo, and at the labor rates these days the labor charge can get to $2,000 or more in a hurry.  So the question is asked: “Can I do this myself in my garage or driveway?”

My first clutch redo was in the late 80’s on a 1978 924 2.0, and since completing that job I vowed that I would NEVER AGAIN try to do it on jack stands on the car port.  Never.  And I have stood by that promise.  Without a lift and trans jack and such, the job is a nightmare – do-able, but a nightmare.

So the answer to the question is simple – yes, you can do it yourself.  But you will probably need help, you will need some tools in addition to the adjustable wrench and broken screwdriver in the drawer in the garage, and you will invariably make up some new words along the way.

The clutch lives in the bell housing at the back of the engine.  There are two ways to get to it – take out the engine or remove the transaxle.  There is a lot of overlap between these two methods, and both involve removing the transaxle and moving the drive tube to the rear to clear the bell housing.  So my choice has always been to leave the engine in the car and get to it from underneath by removing transaxle, moving the drive tube, and removing the bell housing.

So with that in mind, what follows here is NOT a tutorial, but in fact it is an overview on what to expect in doing your clutch job.  With this information, you may be able to make a more informed decision on how to tackle that slipping clutch.

TIME: Budget at least a couple of weekend, maybe more.  Even with help, it will take a while to do all the things that have to be done.  Shops do it in 15-16 hours, so at least double that for a first-time clutch change.

LOCATION: Clear, flat, hard surface.  Don’t try to do this in the dirt.  Also remember that it will be there for a while.  If you can do it inside a garage, opt for that.

TOOLS AND EQUIPMENT: The regular metric sockets, ratchets, universal joints and extensions; metric wrenches; a variety of screwdrivers; Allen head socket adapters; 12-point socket drivers for the rear axles; torque wrench; hydraulic jack(s); tall jack stands; bright lighting; gloves; your favorite spray lubricant and brake parts cleaner; and other things that I have left out, as needed.

PARTS: Complete clutch kit; rear main seal; optional clutch master and slave cylinder.exhaust gaskets from the header to the collector pipe; replacement parts for the stuff that you break.

Now here is the time for the method.  Fasten your seat belts, but your tray tables and seat backs in the full and upright positions.

The bell housing where the clutch lives is trapped between the engine and the driveshaft tube.  As pointed out earlier, you can either (A) remove the engine or (B) back off the drive tube to make room to get to the bell housing.  This method is (B).

UNDER THE HOOD:

• Disconnect the battery.
• Remove the reference sensors.  (Inspect for cracks or bad wiring, replace in pairs if needed.)
• Unplug the Oxygen Sensor connector at the back of the head.  Push the wire out of the engine compartment to under the car.

IN THE PASSENGER COMPARTMENT:

• Remove the trim around the shifter.
• Disconnect the shift bar from the shifter.  Try not to lose the little e-clip or wavy washers.
• Remove the shifter.

UNDER THE CAR:

• Remove the exhaust from the header to the rear of the car.
• Remove both axles.
• Remove the head shield for the catalytic converter.
• Disconnect the shift rod from the transaxle.  Push the rod forward about 10 inches until it is clear of the transaxle.  Manipulate it from the interior where you removed the shifter – flop it over to the left and push it forward in the tunnel.
• Remove both rubber covers on the transaxle and remove the Allen head bolts on the connector between the transaxle and the driveshaft.  Move the connector back so that it is completely on the transaxle input shaft.
• Disconnect the wires to the reverse light switch.  On the Series II cars, disconnect the wire connector to the speedometer drive.
• Remove the four bolts holding the transaxle to the drive tube.
• Put a jack under the transaxle.  If you can, strap it to the jack.
• Remove the bolts that hold the transaxle to the car.  Depending on the model, the transaxle mounting will be different.
• Lower the transaxle and move it out of the way.
• Support the rear of the engine with a jack.
• Remove the starter.
• Remove the clutch slave cylinder.
• Remove the four bolts holding the drive tube to the bell housing.
• From the back of the car, pull the drive tube back.  Rotate it to clear the “ears” at the rear suspension to move it back as far as it will go.

THE BELL HOUSING

• The clutch has a “fork” that engages and disengages the clutch, and it pivots on a shaft.  That shaft has to be removed in order to remove the bell housing.  You will see a small 6mm bolt with a jam nut on it at the bottom of the bell housing facing to the rear of the car.  Loosen the jam nut and remove that bolt.  Under and nearby you will see the end of the shaft – it has a threaded hole in the end of it.  An 8mmx1.25 bolt threads into that hole so that you can remove the shaft.  Thread a bolt into it and, using something to hold on to it, tap it out gently.  This thing may not want to come out.  This is a great opportunity to make up some new words!
• With the shaft removed, you can now remove the bell housing.  There are four bolts holding the bell housing to the engine block.  You will need universal joints, extensions and a big ratchet handle to break these loose and remove them.  One of them at the top can be accessed from above in the engine compartment with a wrench.
• With the bolts removed, pry back the bell housing off of the two dowel pins.  Then wrestle it out.  There may be cables attached to it with 6mm studs and nuts.  Look for these..
• With the bell housing out you are now looking at the clutch.  Remove the nine bolts holding the pressure plate to the flywheel.  The whole thing will come out…it’s heavy, so take care not to drop it on your head.
• Remove the flywheel.  We suggest that you get the flywheel resurfaced at the machine shop.
• With the flywheel out, change the rear main seal…while you are there.

REASSEMBLY

• As they say, reassembly is the reverse of what you have already done.
• Install the seal, flywheel and clutch.
• Position the clutch fork in the bell housing, then reinstall the bell housing with the clutch fork in the proper position, but loose.  Bolt up the bell housing.
• Reinstall the clutch fork shaft and its lock bolt.  Use some of your new words in these two steps.
• Reinstall the clutch slave cylinder at this point.  We suggest putting in a new one.  If you have removed the existing one or have installed a new one, bleed it now, not later.
• Push the driveshaft tube back into position.  This will require someone at the back and you watching the shaft to be sure it is entering the clutch squarely.  Make sure that the tube is oriented correctly, then reinstall the four bolts holding it to the bell housing.  Remove the jack at the back of the engine.
• Reinstall the transaxle including the driveshaft connector and axles.  Reconnect the shift rod, making the sure that the shift rod is facing up in the shifter hole.
• Reinstall the starter making sure that the wiring is properly and correctly routed around the bell housing.
• Reinstall the exhaust using new gaskets at the header.  We suggest using new nuts and bolts, also.
• Route the cable from the Oxygen sensor up to the engine compartment.  Keep the cable away from the exhaust.
• In the interior, reinstall the shifter.  Check to ensure that it shifts through all the gears.
• Under the hood, reconnect the Oxygen sensor.
• Reinstall the reference sensors.  We suggest using new ones.
• Double check everything, reconnect the battery and see what happens.

This provides you with a 10,000 foot overview of what changing the clutch involves.  Can you do it yourself?  Maybe…it’s up to you.

SOME OTHER CONSIDERATIONS

• With the transaxle out, this is a great time to install a short shift kit and shifter from Only944.com.
• If possible, jack up one side of the car at a time and pressure wash the underside before starting this job.  Clean is better than dirty.
• New aftermarket axles are inexpensive.  This may be the time to change them.
• If you don’t know when the oil in the transaxle was last changed, now is the time to do it.
• Take your time, think about each step, and do it right!

Best of luck!