Clutch boost springs: Allocation and grease specification

Gold-coloured bracket (996.423.571.00) and boost spring with purple marking (996.423.081.09 or 996.423.081.11 / see boost spring allocation) must be used only in this combination and installed only in the 911 Carrera (996).

Fig 1: Identifying Boost Spring/Bracket

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Differentiation/identification

1. 2.1 Carrera Mod. '98 / some Mod. '99 

   Boost spring A. Refer to Fig 2. Push rod of boost spring open on one side. Boost spring with purple marking.

   Observe replacement procedure and grease specification.

2. 2.2 Carrera as of current Mod. '99 

   Boost spring B. Refer to Fig 2. Push rod of boost spring closed. Boost spring with purple marking.

   Do not grease any areas as the components are coated.

Fig 2: Identifying Boost Spring Types
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1. 3.1 Carrera Mod. '98 / some Mod. '99 

   The standard boost spring A (push rod on boost spring is open on one side / boost spring painted purple) Spare Part No. 996.423.081.09 is no longer available after existing supplies are used up.

   Boost spring B 996.423.081.11 can then be used as a replacement (closed push rod / boost spring painted purple).

   This boost spring must not be greased.

   Fig 3: Identifying Boost Spring Types

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   When boost spring B is installed for the first time, the optimised clutch pedal 996.423.139.09 must also be used.

   Fig 4: Identifying Boost Spring Hexagon Bolt

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   NOTE:

   • Hexagon bolt 999.423.315.06 and retainer 999.166.022.02 are included with the boost spring to enable it to be attached to the optimised clutch pedal.
   • This scope of delivery is the same as for boost spring type B (as of current Mod. '99).
2. 3.2 Carrera as of current Mod. '99 

   Boost spring B is used as standard and for replacement. Refer to Fig 3.

The following grease specification must be observed during assembly work on the pedals.

1. 4.1 Pedal bearing axle 

   Greasing generally necessary.

   Lubricate sliding surfaces of the bearing bushings X and the pedal bearing axle with Optimol, Optitemp LG 2, Part No. 000.043.203.37. Refer to Fig 5.

   Fig 5: Identifying Pedal Bearing Axle Components

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2. 4.2 Clutch master cylinder push rod 

   Do not grease, as this could result in damage.

3. 4.3 Area around boost spring 

   Depending upon the type of boost spring used, greasing is either necessary or not permitted.

   The following general rule applies: Do not grease coated parts, as otherwise the coating is lost.

   1. 4.3.1 Carrera Mod. '98 / some Mod. '99 

      A. Boost springs installed as standard: 

      Push rod open on one side. Parts uncoated.

      Grease pin for boost spring (arrow) with mating bearing on the boost spring push rod, the boost spring bearing (arrows) and the bearing pins on the boost spring with Optimol, Optitemp LG 2, Part No. 000.043.203.37.

      First remove old grease with solvent naphtha.

      Fig 6: Identifying Boost Spring Greasing Points

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      The boost spring and interior of the boost spring housing are lubricated with a special grease. This grease is not available as a spare part. If necessary, replace the complete boost spring (with housing).

      B. Spare part replacement boost springs 

      Part No. 996.423.081.11 (type used as of current Model '99).

      Distinguishing feature: closed push rod, boost spring with purple marking and hexagon bolt for attachment to the clutch pedal.

      Do not grease any areas as the components are coated.

   2. 4.3.2 Carrera as of current Mod. '99 

      Push rod closed / attachment to clutch pedal by means of a hexagon bolt.

      Fig 7: Attachment Of Boost Spring To Clutch Pedal With Hexagon Bolt

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      Do not grease any points, as the parts are coated.