Coolant Hoses - Engine Bay

Breather / Vent Hose. 

The Genuine Porsche Breather / Vent Hose is a replacement hose used within the engine cooling and coolant expansion system on selected Porsche Boxster models.

Fits:

• Porsche Boxster 986 2.5L 1997-99
• Porsche Boxster 986 2.7L 1999-02
• Porsche Boxster S 986 3.2L 1999-02
• Porsche Boxster 986 2.7L 2003-04
• Porsche Boxster S 986 3.2L 2003-04
• Porsche Boxster 987 2.7L 2005-06
• Porsche Boxster 987 S 3.2/3.4L 2005-06

Diagram Ref No 21

Despite being described as a breather hose, this component is part of the cooling system rather than the engine crankcase ventilation system. Its purpose is to provide a controlled path for coolant and displaced air within the cooling circuit, helping the system vent correctly and maintain reliable coolant circulation.

As the engine heats and cools, coolant expands and contracts while small amounts of trapped air may move through the system. The vent hose helps manage this movement between cooling-system components so that unwanted air pockets do not interfere with normal coolant flow.

With age, repeated heat cycles and prolonged exposure to coolant, the original hose can harden, crack, split or begin leaking around its connections. Replacing a deteriorated hose helps restore a sealed cooling circuit and reduces the risk of coolant loss or air entering the system.

What This Product Does:
The coolant breather hose forms part of the engine's liquid-cooling system.

It is designed to:

• Provide a vent path within the cooling circuit.
• Help move displaced air through the cooling system.
• Assist with coolant circulation between connected components.
• Help prevent unwanted air pockets forming within the cooling system.
• Maintain a sealed coolant circuit.
• Carry coolant where required during expansion and contraction.
• Support correct operation of the expansion-tank and cooling-system arrangement.
• Replace a cracked, leaking or hardened original hose.
• Help maintain correct coolant level and system pressure.

Symptoms Of Wear Or Failure:
Possible symptoms include:

• Visible coolant leakage.
• Dampness around the hose or its connections.
• Dried coolant residue around fittings.
• Gradual reduction in coolant level.
• Coolant smell around the engine compartment.
• Hose becoming hard or brittle.
• Visible cracking.
• Splits in the hose.
• Swelling or deformation.
• Leakage when the cooling system becomes hot and pressurised.
• Air repeatedly entering the cooling system.
• Coolant-level warning appearing.
• Engine temperature becoming less stable.
• Coolant collecting around nearby components.
• Steam or coolant vapour from the engine area in severe cases.

Similar symptoms can also be caused by the expansion tank, cap, water pump, radiator hoses or other cooling-system components, so the actual source of the leak should be confirmed.

Why Replacement Matters:
The cooling system needs to remain sealed to maintain the correct coolant volume, pressure and circulation.

A leaking vent hose can allow coolant to escape and may permit air to enter the system as the engine cools.

Replacing a damaged hose helps restore:

• A sealed cooling circuit.
• Correct coolant retention.
• Proper cooling-system venting.
• Stable engine temperature.
• Reliable coolant circulation.
• Reduced risk of air pockets.
• Long-term cooling-system reliability.

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Fits:

Porsche 987.2 Boxster 2008-12
Porsche 987C.2 Cayman 2008-12

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Diagram ref no 11

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Porsche 987.2 Boxster 2.9L / 3.4L 2009-12
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Diagram ref no 13

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Porsche 997.2 Carrera 2009-12
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Porsche 991.1 Carrera 2012-16
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Porsche 991 Turbo 2014-20
Porsche 992.1 Carrera 2019>>
Porsche 992 Turbo / Turbo S 2020>>

Porsche 987.2 Boxster 2.9L / 3.4L 2009-12
Porsche 981 Boxster 2012-16
Porsche 981 Boxster Spyder 2016
Porsche 982 (718) Boxster GTS 4.0L 2017>>
Porsche 982 (718) Boxster Spyder 2019>>

Porsche 987C.2 Cayman 2.9L / 3.4L 2009-12
Porsche 981C Cayman 2014-16
Porsche 981C Cayman GT4 2016
Porsche 982C (718C) Cayman GTS 4.0L 2017>>
Porsche 982C (718C) Cayman GT4 2019>>

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Diagram ref no 1

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Fits:
Porsche 981 Boxster 2012-16
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Diagram ref. 6.

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Diagram ref no 15

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Diagram ref no 3

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Diagram ref no 3

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Coolant Pipe Connection Adapter. 

The Genuine Porsche Coolant Pipe Connection Adapter 9A110613201 is an original equipment replacement cooling system component designed for Porsche Boxster 987.2 and Cayman 987.2 models. Manufactured to Porsche's original specifications, this adapter provides a secure connection within the engine's coolant pipe assembly, helping maintain reliable coolant circulation and cooling system integrity.

Fits:

• Porsche Boxster 987 MKII 2.9L 2009-12
• Porsche Boxster S 987 MKII 3.4L 2009-12
• Porsche Cayman 2.9L 987C MKII 2009-12
• Porsche Cayman S / R 3.4L 987C MKII 2009-12  

Diagram Ref No 12

Also referred to as a coolant connection piece or engine coolant outlet flange, this component forms part of the cooling system pipework and helps maintain a leak-resistant connection between associated cooling circuit components.

The adapter is exposed to engine heat, coolant pressure, vibration and repeated temperature changes during normal operation. Over time, the original component or its sealing surfaces may deteriorate, potentially resulting in coolant leaks or reduced cooling system reliability.

Ideal for replacing damaged, cracked, leaking or deteriorated original adapters, this genuine Porsche component provides a direct OE replacement for maintaining the cooling system's original configuration.

What This Product Does:
The coolant pipe connection adapter forms part of the engine cooling system, providing a connection point between the associated coolant pipework and cooling circuit components.

It helps maintain a secure, sealed passage for coolant while supporting the cooling system's ability to regulate engine temperature effectively.

Its key functions include:

• Coolant Pipe Connection: Provides a secure connection between designated coolant pipes and associated cooling system components.
• Coolant Circulation: Allows coolant to pass through the connection point, supporting continuous circulation within the cooling circuit.
• Leak Prevention: Helps maintain a sealed connection to reduce the risk of coolant escaping.
• Cooling System Pressure: Supports the integrity of the pressurised engine cooling system.
• Engine Temperature Regulation: Contributes to efficient engine cooling by maintaining a reliable coolant flow path.
• Secure Component Fitment: Helps keep the connected coolant pipework correctly positioned and secured.
• Thermal Durability: Designed for exposure to engine operating temperatures and repeated heating and cooling cycles.
• Original Equipment Compatibility: Maintains the factory-designed cooling system connection and installation arrangement.

Symptoms Of Wear Or Failure:
Over time, prolonged exposure to engine heat, coolant pressure and vibration can cause coolant pipe adapters and their associated seals to deteriorate.

Common signs include:

• Visible Coolant Leaks: Coolant escaping around the adapter or adjoining pipe connections may indicate a damaged component or failed seal.
• Low Coolant Warning: Loss of coolant through a leaking connection may trigger a dashboard warning.
• Frequent Coolant Top-Ups: Repeated coolant loss can indicate a leak around the adapter or another cooling system component.
• Cracked or Damaged Adapter Housing: Physical cracks, fractures or deterioration may compromise the connection's ability to remain sealed.
• Deteriorated Sealing Surfaces: Worn, damaged or contaminated sealing areas may allow coolant to escape.
• Coolant Residue Around Connections: Dried coolant deposits or staining near the adapter may indicate previous or ongoing leakage.
• Loose or Insecure Connection: Damaged retaining components or worn connections may allow unwanted movement within the assembly.
• Coolant Smell from the Engine Bay: Escaping coolant contacting warm engine components may produce a distinctive sweet smell.
• Engine Overheating: Significant coolant loss can reduce the cooling system's ability to regulate engine temperature effectively.
• Fluctuating Engine Temperature: Coolant loss or air entering the cooling circuit may contribute to irregular temperature readings.
• Steam from the Engine Compartment: A severe leak may allow coolant to contact hot engine components, producing visible steam.

Why Replacement Matters:

• Replacing a worn or leaking coolant pipe connection adapter is essential for maintaining the reliability and integrity of your Porsche's engine cooling system.
• The cooling system relies on secure, leak-resistant connections between its hoses, pipes and associated components. If a connection adapter becomes cracked, damaged or incorrectly sealed, coolant can escape, reducing the system's ability to maintain the correct operating pressure and coolant level.
• Even a minor coolant leak can become progressively worse, particularly as the cooling system undergoes repeated heating and cooling cycles. Continued coolant loss may eventually lead to engine overheating and damage to important engine components.
• A severely damaged connection adapter can also fail unexpectedly, potentially causing rapid coolant loss and an unplanned vehicle breakdown.
• Installing a genuine Porsche replacement adapter helps restore the original cooling system connection, ensuring the component fits correctly within the specified pipework arrangement.
• Replacing damaged adapters and inspecting associated seals, hoses and retaining components can help prevent recurring coolant leaks and reduce the risk of more expensive cooling system or engine repairs.
• For Porsche Boxster and Cayman owners, maintaining the cooling system is particularly important for ensuring consistent engine temperature regulation during everyday driving and demanding operating conditions.
• The Genuine Porsche Coolant Pipe Connection Adapter 9A110613201 provides an original equipment replacement solution, helping maintain secure coolant connections, reliable cooling performance and long-term engine protection.

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Diagram ref no 12

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Diagram ref no 1

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Diagram ref no 1

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Diagram ref no 11

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Diagram ref no 26

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