Home Porsche Repair Porsche 911 (964): Enthusiast's Companion

©2002 Robert Bentley, Inc. We encourage visitors to link to this page if you’d like to share this information with others. Please do not copy this excerpt to other web sites. It is protected by copyright and represents significant resource investment by Bentley Publishers.

(4 page excerpt from Chapter 3)

Please read these warnings and cautions before proceeding with maintenance, repair or modification work.

Lubrication system

Oils

As of year 2000, the oils approved for use in all Porsche engines for model years 1973 to 2000 are listed below.


Approved engine oils
Castrol Syntec5W 50
Castrol GTX5W 30, 10W 30, or 15W 50 (Europe only)
Exxon Superflo Supreme15W 40
Mobil 15W 30 or 10W 30
Sun Oil / Sunoco Synthro Gold5W 40
Texaco / Havoline Formula 3 Synthetic5W 40

CAUTION —
0W 30 and 0W 40 is only approved for the 996 series and not recommended for tired engines. This oil is very thin even when very cold.

Oil system

The components of the normally aspirated engine lubrication system are:

  • Engine driven oil pump
  • Oil filter
  • Oil tank
  • Oil thermostat and plumbing
  • Oil cooler assembly and plumbing
  • As with all previous 911 series engines, the M64 and M30 engines are dry-sumped. The oil is stored externally in an oil tank, located forward of the right rear wheel in the wheel arch. When the engine is shut down, the oil is returned to the external tank. Only a small residue (approximately 2 litres) of oil remains inside the engine. This is important to remember at oil change time.


    Engine oil capacity
    Oil and filter change9 litres (9.5 US qt)
    Complete refill11.5 litres (12.5 US qt)

    CAUTION —
    During a routine oil change service, filling the engine with more than 9 litres of oil will cause the system to be overfilled. Smoke out of the exhaust will result after each start.

    Overfilling with oil can cause problems which are described elsewhere in this book.


    Oil filter location
    Normally aspirated engineright side of engine bay
    Turbo engineright underside of engine (access from underneath)

    Oil cooler system

    The oil cooler system of the 964 consists of components mounted at the right side and right front of the car.

    NOTE —
    The main difference between the 964 oil cooler system and systems used on previous 911 series is that there is no engine mounted oil cooler in the 964 engine.

    An oil cooler and two-speed blower assembly is mounted forward of the right front wheel. The blower is on the outside of the oil cooler. The entire assembly is mounted at 90° to the front of the 964.

    The oil cooler blower provides additional or backup cooling.

    Installed into the oil cooler is a temperature sensor which supplies a signal to the air conditioning and heating control unit. At a predetermined oil temperature the control unit will activate the low speed function of the oil cooler blower. If oil temperature in the cooler continues to increase, at a specific temperature the control unit will switch the blower to high speed.

    NOTE —

  • Under normal driving conditions the oil cooler blower will never switch to high speed.
  • The 964 air conditioning and heating control unit responds to oil temperature in the oil cooler, not in the engine.
  • The oil cooler is connected to the oil thermostat and the oil tank in the rear of the car by two oil lines. These run to the back along the right side of the car.

    1. Oil return line (to oil tank)4. Oil cooler blower
    2. Oil supply line (to oil5. Oil thermostat
    cooler)6. Oil cooler temperature
    3. Oil cooler sensor

    Of the two solid oil lines from the thermostat to the oil cooler, the inside one (1) is the supply from the thermostat (hot), and the outside one (2) is the return to the oil tank. In the front fender, the hot line is also the inside one. This is not obvious when the cover at the bottom rear of the front wheel well is removed. The inside hot line is connected to the flexible line which goes to the front oil cooler connection. This is the more vertical one. The angled connector on the rear of the oil cooler is supplied with cooled oil from the bottom of the cooler.

    Oil cooler thermostat


    One oil line connects the oil cooler to the external oil tank. This is the return line. (There is a straight through connection for this pipe in the oil thermostat.)

    The other oil line is connected to the engine via a thermostat, mounted to the right lower body structure forward of the external oil tank.

    A bimetallic oil temperature sensor mechanically opens the thermostat at a specific oil temperature. Oil flow from the engine is then diverted to the oil cooler first before returning to the oil tank.

    The specifications for the oil thermostat changed over the years. The 1989 to 1991 components are interchangeable, although it is always better to replace any part with a later version. Going backwards is not recommended. This particularly applies to 964 owners who use parts from wrecks.


    Oil cooler thermostat (Porsche part nos.)
    1989 - 1990964 207 047 03
    1991964 207 047 05
    1991964 207 047 06
    1992964 207 047 07
    1993964 207 047 08
    Thermostat insert 1992 - 1994964 207 349 01

    CAUTION —
    Starting with the 1992 model year, the mounting of the thermostat was changed and these are not interchangeable with the pre-1992 versions

    End of excerpt

    ©2002 Robert Bentley, Inc. We encourage visitors to link to this page if you’d like to share this information with others. Please do not copy this excerpt to other web sites. It is protected by copyright and represents significant resource investment by Bentley Publishers.