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Porsche > Engine Cooling > Coolant Hoses and Pipes (Front engine cars) > Engine Block Hoses >

O-Ring 11x2,5 Water Coolant Breather Line. Porsche 957 / 958 Cayenne / 970 Panamera / 95B Macan  ❭  99970758640

O-Ring 11x2,5 Water Coolant Breather Line. Porsche 957 / 958 Cayenne / 970 Panamera / 95B Macan - 99970758640 - ORS34382
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Product Information
Product Information

O-Ring – 11 x 2.5mm Water Coolant Breather Line
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Ensure a reliable, leak-free cooling system with this OE Match O-Ring, measuring 11 x 2.5mm. Designed as a direct replacement for the original seal used on the water coolant breather line.

Fits:

  • Porsche 957 Cayenne S / GTS 4.8L 2007-10
  • Porsche 957 Cayenne Turbo / Turbo S 4.8L 2007-10
  • Porsche 958 Cayenne Turbo V8 4.8L Petrol (500Hp) 2010-17
  • Porsche 958 Cayenne Turbo S V8 4.8L Petrol (550Hp) 2010-17
  • Porsche 970.1 Panamera S V8 4.8L 2009-13
  • Porsche 970.1 Panamera 4S V8 4.8L 2009-13
  • Porsche 970.1 Panamera GTS V8 4.8L 2011-13
  • Porsche 970.1 Panamera Turbo V8 4.8L 2009-13
  • Porsche 970.1 Panamera Turbo S V8 4.8L 2009-13
  • Porsche 970.1 Panamera Diesel V6 3.0L 2011-13
  • Porsche 970.1 Panamera S Hybrid V6 3.0L 2011-13
  • Porsche 970.2 Panamera V6 3.6L 2WD (310Hp) 2014-16
  • Porsche 970.2 Panamera 4 V6 3.6L 4WD (310Hp) 2014-16
  • Porsche 970.2 Panamera S V6 Turbo 3.0L 2WD (420Hp) 2014-16
  • Porsche 970.2 Panamera S V6 Turbo 3.0L 2WD Executive 2014-16
  • Porsche 970.2 Panamera 4S V6 Turbo 3.0L 4WD (420Hp) 2014-16
  • Porsche 970.2 Panamera 4S V6 Turbo 3.0L 4WD Executive 2014-16
  • Porsche 970.2 Panamera GTS V8 4.8L 4WD (440Hp) 2014-16
  • Porsche 970.2 Panamera Turbo V8 4.8L (520Hp) 2014-16
  • Porsche 970.2 Panamera Turbo V8 Executive 2014-16
  • Porsche 970.2 Panamera Turbo S V8 4.8L 2014-16
  • Porsche 95B.1 Macan GTS Petrol 3.0L V6 (360Bhp) 2014-18
  • Porsche 95B.1 Macan Turbo 3.6L V6 (400Bhp) 2014-18

Diagram ref no 12

Although small, this sealing ring plays a vital role in maintaining the integrity of the cooling system. It creates a watertight seal between the breather line and its mating components, preventing coolant leaks while allowing the cooling system to maintain the correct operating pressure. Replacing ageing or damaged O-rings during cooling system maintenance helps prevent coolant loss, overheating and expensive engine repairs.

Manufactured from high-quality, coolant-resistant elastomer, this OE Match O-ring is designed to match the dimensions and performance of the original Porsche component for dependable long-term sealing.

What Does the Water Coolant Breather Line O-Ring Do?

The coolant breather line O-ring seals the connection between coolant pipes and breather line fittings within the engine's cooling system.

Its functions include:

  • Preventing coolant leaks.
  • Maintaining cooling system pressure.
  • Ensuring efficient coolant circulation.
  • Preventing air from entering the cooling system.
  • Supporting correct engine operating temperatures.
  • Helping maximise cooling system efficiency.

A correctly sealing O-ring is essential for maintaining the performance and reliability of the engine cooling system.

Why Does the O-Ring Need Replacing?

Over time, coolant seals are subjected to constant temperature fluctuations and coolant exposure, causing them to deteriorate.

Common causes of failure include:

  • Heat cycling.
  • Age-related hardening.
  • Loss of elasticity.
  • Coolant chemical degradation.
  • Damage during removal.
  • Compression set after years of service.
  • Cooling system repairs requiring seal replacement.

As with most sealing components, O-rings should always be replaced once removed.

Symptoms of a Failing Coolant Breather Line O-Ring

Signs of a worn or damaged seal include:

  • Coolant leaks around the breather line.
  • Pink, white or dried coolant residue.
  • Low coolant warning messages.
  • Frequent coolant top-ups.
  • Sweet coolant smell from the engine bay.
  • Reduced cooling system pressure.
  • Small coolant drips after driving.

Replacing the O-ring at the first sign of leakage helps prevent overheating and further cooling system damage.

When Should the O-Ring Be Replaced?

Replacement is recommended whenever:

  • The coolant breather pipe is removed.
  • Cooling system components are replaced.
  • A coolant leak is diagnosed.
  • Carrying out thermostat or water pump repairs.
  • Performing preventative cooling system maintenance.
  • Rebuilding or servicing the engine.

Installing a new O-ring during reassembly ensures a reliable seal and reduces the risk of future coolant leaks.



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