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WM 1001IN Information on working with aluminium screws and magnesium components - IMPORTANT!

Tools





Technical values





Information on working with aluminium screws

Information on aluminium screws

Information

Aluminium screws and steel screws have different properties!

- Most aluminium screws are identified on Porsche V-engines by an internal Torx screw with internal pin ( => Aluminium screw on V-engines ). Aluminium screws can be identified differently on transmissions, on the chassis and on engines from other manufacturers. The design-related distinguishing features can be omitted if necessary.

- One differentiating feature is that aluminium screws are lighter than steel screws of the same size (e.g. screws used in bar ignition modules).

- Aluminium screws are different from steel screws in that they are not magnetic. If in doubt, check the screws using a magnet.

- The aluminium screws used at present have the additional marking RIBE (manufacturer) and AL9 (strength) on the screw head. => Aluminium screw on V-engines

- Screws with an internal pin can be loosened and tightened using commercially available bit inserts with a hole (safety bits).





Aluminium screw on V-engines

- Aluminium screws must be used only once. Replace the screws whenever they have been loosened.

- Aluminium screws must always be tightened in two steps (torque and torque angle) or require a special yield-point wrench Electronic torque wrench 9768. The specified tightening torques and torque angles must always be observed. The extent to which a screw is tightened can be limited using a yield-point wrench.

- There is no need to tighten by clicking once as this may cause irreparable damage to the screw.

- Sealants that can come into contact with aluminium screws in threaded bores must be approved for use with aluminium screws by Porsche => if this is not observed, there will be increased friction in the screw thread and the aluminium screw will break.

- Aluminium screws must not be fitted using tightening parameters for steel screws => the aluminium screw will break.

- Screw threads must be perfectly clean. Sealant residue or chips increase the friction coefficient => the aluminium screw will break. Blow out thread holes.

Aluminium screws




Information on working with magnesium components

The following components are made of magnesium:





Magnesium components (status 04/2009)





WARNING

Magnesium chips

- Danger of fire

-> Do not collect magnesium grinding dust, magnesium chips or abraded material in open containers. Use containers that can be sealed tightly.
-> A small amount of chips produced when re-cutting threads, for example, is not important.
-> If larger amounts of magnesium chips and dust are produced, these must not be stored dry.
-> The dust and chips must be removed by suction during extensive grinding work.
-> Avoid making sparks when working with magnesium.
-> Extinguish magnesium fires using fire extinguishers for metal fires rather than water.

Information

- Magnesium is corrosive in the event of contact with steel, copper or aluminium with a high copper content.

- Damaged magnesium threads must be repaired using aluminium threaded bushes without copper content that have been approved by Porsche.

- Magnesium components must only come into contact with screws (aluminium screws, coated screws), lubricants and sealing compounds that have been approved by Porsche (risk of corrosion).

- Heat-resistant copper paste cannot be used (risk of corrosion).

- Magnesium components must not come into contact with steel parts (panels, clamps, etc.) (risk of corrosion). => Possible corrosion on valve cover if steel plate clips are used inadvertently





Possible corrosion on valve cover if steel plate clips are used inadvertently

- Only use type-specific accessories and spare parts approved by Porsche. Do not use previously used parts or parts from the "tool kit".

- Always keep threaded joints and contact surfaces of magnesium components dry. Blow-dry threaded bores immediately if threaded joints are opened.