924/944/968 Frequently Asked Questions

944 Clutch Replacement Procedure

The following note was created by Michael Kehr. It has since been slightly edited to update tool sources, etc. Prices are all in USD. Prices and part numbers were correct in '94 but many are likely to have changed in the interim.

General Information

The purpose of this procedure is to supply basic but complete information for clutch replacement on a '86 951, with one- or two-piece crosspipe.

At the time this was written, I had just recently finished a complete clutch job on my '86 951, which included replacing the throwout bearing, pressure plate, clutch disc, pilot bearing, guide sleeve, and the two needle bearings on the release lever.

I am posting my experiences so I may help others who are mechanically inclined but cannot afford the $1,400.00 plus labor to do the job. This procedure applies to all 944-series cars, with some exceptions.

Porsche sets the shop time at

23 hours (single-piece cross-pipe) @ $55.00 = $1265.00 ~
16 hours (two-piece cross-pipe) @ $55.00 = $880.00 ~
~ Approximate labor rate

I completed the entire job in two weeks working part time, which included replacing the right motor mount, cleaning the underbody and transmission, undercoating, and eliminating all corrosion. Some steps will be frustrating if you have never done this kind of work on this type of car. Take your time, keep organized, and most important have patience - you'll need it!

I would like to thank fellow list member Mark Sundt for all his help and support throughout this job. His patience and insight are greatly appreciated. Also I would like to thank Milo Dorr, Steve Timmons, Kevin Gross, Jim Selders and Doug Dyakar. Without the help of these people I would never have been able to do this job. Thanks also to Stan Hanks and his informative Archives.

The job should not be undertaken by those without some mechanical ability. It is not an extremely difficult job, but requires many steps especially if your car still has the single part cross pipe. Organization is important! Safety is also very important, when working under a car supported by jack stands. Take time and care when raising the car with the hydraulic jack, utilizing the proper jack points. A good idea would be a secondary means of support, such as concrete blocks under the wheels.

I am going to explain this procedure in detail in hopes that I can help other list members do this job. Reviewing and researching before you start is a good way to familarize yourself with the car, and will make you more confident, resulting in a sucessful job. The clutch replacement on my 951 was the second time I have ever worked on a car, other than basic maintenance, the first being the replacement of the front struts and strut bearings.

I will also list the tools needed and where to find them. Part numbers will be given, along with chemicals needed, research material sources and torque specs. I will refer to the Haynes 944 manual, the 944 Factory Workshop Manuals (6 volumes) including the Turbo supplement and Mark Sundt's notes, used with his permission. I have also included "Hints and Notes" sections to point out important areas.

I tried to make this information as accurate as possible. If there are other suggestions or hints that will make this account more complete feel free to add your comments to the list.

Good luck!

Tools

Having the proper tools when working on a Porsche is very important. Using good quality tools is also very important - I have found out the hard way! I was frustrated more times then I can remember while doing this job. Now after the job is complete I know what tools I should have used, and now you will know before you start. Of course not all tools listed are mandatory, but the ones listed below will make life easier.

I have found that most Sears Craftsman tools are very poor in quality. The sockets and wrenches work ok, but the ratchets and mechanical tools are sub-standard in quality. I speak about the "newer" tools; I know that the older product is much better. Hazet and Heyco are the German tools used to assemble German cars, they are very good and are made to fit in some of those tight places. Snap-On, Mac, Matco, S&K/Facom are good tools, especially Snap-On (great quality and big bucks). There are very few special tools required to do this job. A somewhat complete list of tools and the resources for them will follow.

Ratchets

Universals

Extensions

Sockets

Adapters

Wrenches

Drivers

Special Tools

Miscellaneous

Notes

Tool Sources

Chemicals and Lubricants

Chemical and Lubricant Suppliers

Reference Material

Reference Suppliers

A Note on Reference Material
I would at least purchase the Haynes service manual. I would suggest having access to a friend's set of workshop manuals and parts fiche, if possible. Though you may not need much after you use these notes.

Parts

quantity part number description cost note
1 951.116.082.01 release bearing   1
1 951.116.011.15 clutch disc   1
1 951.116.023.01 pressure plate   1
1 931.102.111.00 pilot bearing $17.95 1
1 016.141.181 guide sleeve $15.99 1
2 999.201.213.00 needle bearing $12.99  
12 999.510.012.02 cheesehead bolt $0.85 2
4 944.110.163.05 intake manifold gasket   4
1 944.110.901.00 fuel injector seal kit   4
1 944.111.205.03 seal ring - large $22.10 3
4 944.111.205.04 seal ring - medium $17.42 3
1 931.123.195.00 seal ring - small $7.84 3
1 951.123.134.02 sealing band $24.40 3

Notes

  1. I replaced all of these parts because of the labor involved to access them.
  2. Replace any hardware that becomes damaged upon removal.
  3. Must replace exhaust sealing rings & gaskets if disassembled.
  4. If intake manifold removed.

Parts Sources

I purchased the EuroSelect clutch parts, which are a Sachs Product. The clutch disc had the six smaller springs in the center with the four larger on the outside. The Porsche part is identical. The only difference I could tell is that the Porsche part carries a two-year warranty while the EuroSelect is one year. The Porsche part is almost double the price. Check out Excellence magazine for current prices & other vendors.

Procedure

First it needs to be determined if you have a single- or two-part cross-over pipe. The diagram is in the factory workshop manual Turbo supplement, pg. 30-3. All '86 951's originally had the single part cross-pipe. Under warranty PCNA replaced the non-bellowed type headers, when they cracked, with the improved "accordian" style. This was done for the first 5 years or 50K miles. The one-pa`rt cross pipe was updated to the current two-part type under "hidden" warranty with the headers.

The old style did not have a seperate pipe going up to the wastegate. The clutch bellhousing cannot be removed without this piece removed! Believe me I tried. So if you have the single cross pipe, it must be completely removed all the way up to the turbocharger. This involves removing the intake manifold, and lots more stuff in the engine compartment, in order to access the turbo exhaust bolts. This creates a lot more work! Let's hope you have the new two-part cross-pipe!

Note
 
As parts are removed, label and store them in plastic parts bags. Be organized!
Hint
 
Be careful when removing and installing hardware in and around engine compartment. There are many "black holes" where nuts and misc. items just disappear. I used a shop rag just under the working area to catch falling objects. A telescoping magnetic pick-up tool works great for hardware retrieval!
  • Place covers over fenders.
  • Disconnect battery by removing ground cable from the battery.

Cruise Control Cable

If your car is equipped with the cruise control option:

  • Disconnect cable on cruise control motor.
    1. Remove retaining clip on cable.
    2. Loosen and slide cable housing locking nut toward motor.
    3. Pull end of cable housing through hole, slide cable through split in cable housing mount.
    4. Remove cruise control cable clamp, on manifold.

Fuel Rail and Injectors

  • Pull off vacuum hoses on pressure regulator and pressure damper. Inspect at same time; replace if damaged.
  • Remove fuel rail. Be careful of plastic pintel caps at the end of each injector.
  • Remove distributor cap with spark plug wires (I left the cap on and just removed the spark plug ends wires only).
  • Disconnect fuel connections to fuel rail. There are two: one for supply, one for return. One line is secured by a hose clamp, the other is fitting. Try to catch fuel that leaks out of the system. I covered the open line ends with plastic bags and wrapped with electrical tape.
    Danger
     
    Be careful with fumes from fuel. Work in a well-ventilated area, and not around gas pilot lights, eg, from a furnace!
  • Fuel Injectors: carefully remove fuel rail from injectors starting at one end. More fuel will spill out of rail. Next remove injectors one at a time from the intake manifold Set aside.

Intake Manifold

  • Remove the hose clamps on many intercooler connections.
  • Remove black aluminium intercooler tubes.
  • Disconnect electrical connection to throttle body.
  • Remove the throttle and cruise control cables with the clamp on intake manifold.
  • Remove the vacuum tube at throttle body (underneath).
  • Remove the M8 bolt at the front of the manifold.
  • Remove the M6 bolt at the dipstick.
  • Remove the dipstick guide tube.
  • Remove the two M6 allen bolts at the oil filter.
  • Remove the M6 allen bolt and electrical harness at the back of the manifold.
  • If the intake manifold will not come loose, tap it carefully with rubber mallet to free manifold from the gaskets. Cover intake ports. Turn manifold over so turbo- charger is visible.
  • Remove the shield for master cylinder: two M6 bolts bolts, three nuts. It is difficult to remove, has sharp edges, but will bend to facilitate removal. Good luck! It is easier to access the bottom two nuts when car is lifted.

Exhaust System

Transmission

Clutch

Pilot Bearing

The pilot bearing is a bearing that supports the rear of the crankshaft. As you can see it has taken a lot of work to get to this point, therefore it is a good idea that this part be replaced.

Guide Sleeve

Needle Bearings

Flywheel Inspection

Clutch Installation

The sequence for assembly of central tube, transmission, exhaust system, etc. is the reverse of removal, with some notes below.

Intake Manifold

Assembly is reverse of disassembly, with some notes provided below.

Torque specificiations

Clutch
Reference mark and speed sensors: 6 ft-lbs. / 8 Nm.
Slave cylinder to clutch housing; 15 ft-lbs. / 21 Nm.
Central tube flange to clutch housing: 30 ft-lbs. / 42 Nm.
Starter to clutch housing: ?
Transmission
Transmission carrier to body: 34 ft-lbs. / 46 Nm.
Bracket to transmission: 17 ft-lbs. / 23 Nm.
Guide sleeve (drive shaft to transmission input shaft): 58 ft-lbs. / 80 Nm.
Shift rod to transmission 15 ft-lbs. / 21 Nm.
Shift lever plate to central tube: 15 ft-lbs. / 21 Nm.
CV joint bolts (drive axles to transmission): 30 ft-lbs. / 41 Nm.
Speedometer socket to transmission: 30 ft-lbs. / 42 Nm.
Engine
Intake manifold to engine 14 ft-lbs. / 20 Nm
DME
Oxygen sensor: 36 - 43 ft-lbs. / 50 - 60 Nm.
All Other
M6: 6 + 1.4 ft-lbs. / 8 + 2 Nm.
M8: 14 + 1.4 ft-lbs. / 20 + 2 Nm.
M10: 29 + 3.6 ft-lbs. / 40 + 5 Nm.

Sources

If you have any questions/corrections/suggestions please feel free to contact me, Mike Kehr
e-mail: mikehr@earthlink.net
home phone: +1 609 645 8167

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