Coolant Hoses - Engine Bay

Coolant Connection Piece Adapter. 

The Genuine Porsche Coolant Connection Piece Adapter (Part Number: 9A110613100) is an original equipment engine cooling system component designed for selected Porsche 911 (997.2) Carrera and Turbo models.

Fits:

• Porsche 997 MKII Carrera C2 3.6L 2009-12
• Porsche 997 MKII Carrera C4 3.6L 2009-12
• Porsche 997 MKII Carrera C2S 3.8L 2009-12
• Porsche 997 MKII Carrera C4S 3.8L 2009-12
• Porsche 997 MKII Turbo 2010-13  

Diagram Ref No 12

Also referred to as an engine coolant pipe adapter, coolant connection piece or coolant outlet flange, this component forms part of the engine's coolant pipework and provides a secure connection between associated cooling system components.

Manufactured to Porsche's original equipment specifications, the adapter is designed to maintain the correct coolant flow path while providing a reliable, leak-resistant connection within the engine cooling circuit.

The Porsche 997.2 uses a liquid-cooled flat-six engine, which relies on continuous coolant circulation to regulate operating temperatures and prevent excessive heat accumulation.

During normal operation, the coolant pump circulates coolant through the engine and associated cooling components. The coolant absorbs engine heat and transfers it through the cooling system, allowing the engine to operate within its intended temperature range.

The coolant connection piece provides a defined passage and connection point within this system, helping maintain the integrity of the coolant circuit.

The component is listed in Porsche's engine assembly carrier and water pipe diagram, where it connects with the associated coolant pipework and retaining components.

During operation, the adapter is exposed to engine heat, coolant pressure, vibration and repeated temperature changes.

Over time, the connection piece or its associated sealing components may deteriorate through thermal cycling, corrosion, mechanical damage or incorrect installation.

A damaged adapter may allow coolant to escape, resulting in a gradual reduction in coolant level, visible leakage or cooling system pressure loss.

If coolant loss becomes severe, the engine may overheat, potentially causing significant mechanical damage.

Replacing a worn or damaged coolant connection piece with a Genuine Porsche component helps restore a secure coolant connection, maintain cooling system integrity and support reliable engine temperature regulation.

Ideal for coolant leak repairs, engine cooling system maintenance and Porsche 997.2 engine refurbishment, this Genuine Porsche adapter provides a factory-specified replacement for compatible vehicles.

What This Product Does:
The coolant connection piece adapter is part of the engine's liquid cooling system.

Its primary function is to provide a secure connection and passage between the designated coolant pipes and associated engine cooling components.

As coolant circulates through the engine, it absorbs heat from the engine's internal passages.

The heated coolant is then directed through the cooling circuit, allowing heat to be transferred away from the engine.

The adapter helps maintain the correct coolant pathway between its connected components.

Its main functions include:

• Connecting coolant components: Provides the specified connection between the engine cooling circuit and associated pipework.
• Maintaining coolant circulation: Allows coolant to pass through the intended connection.
• Preventing coolant leakage: Supports a secure, leak-resistant joint when correctly fitted and sealed.
• Maintaining cooling system pressure: Helps preserve the integrity of the pressurised coolant circuit.
• Supporting engine temperature regulation: Contributes to the reliable circulation of coolant through the engine.
• Providing correct pipe positioning: Maintains the specified connection geometry within the engine assembly.
• Supporting reliable hose attachment: Works with the appropriate connected coolant hose or pipe arrangement.
• Accommodating normal operating conditions: Functions within the designed temperature and pressure conditions of the cooling system.
• Preserving factory cooling system routing: Maintains Porsche's intended coolant connection arrangement.
• Supporting cooling system servicing: Allows a damaged connection piece to be replaced without unnecessarily replacing unrelated components.

The adapter does not circulate coolant independently.

Coolant movement is produced by the coolant pump, while operating temperature is regulated by the thermostat and associated cooling system components.

Symptoms Of Wear Or Failure:
The coolant connection piece is exposed to repeated temperature changes, cooling system pressure and engine vibration.

Although designed for long service life, the component or its associated seals may eventually deteriorate.

Common symptoms and signs of a faulty coolant connection piece include:

• Visible coolant leakage: Coolant may escape from the adapter or its connection points.
• Falling coolant level: The expansion tank may require frequent topping up because of coolant loss.
• Coolant residue: Dried coolant deposits may appear around the adapter or nearby pipework.
• Sweet coolant smell: Escaping coolant may produce a noticeable odour around the vehicle.
• Coolant beneath the vehicle: Leaking coolant may drip onto surrounding components or the ground.
• Engine temperature rising: Significant coolant loss may reduce the cooling system's ability to control engine temperature.
• Coolant warning message: The vehicle may display a low coolant warning if the level drops sufficiently.
• Loss of cooling system pressure: A defective connection may prevent the system from retaining its intended pressure.
• Cracked adapter housing: Physical damage or ageing may cause cracks in the connection piece.
• Damaged sealing surfaces: Scratches, corrosion or deformation may prevent the joint from sealing correctly.
• Loose coolant connection: Damaged retaining components may affect the security of the connected pipe or hose.
• Deteriorated sealing ring: A worn or displaced seal may allow coolant to escape even when the adapter itself remains intact.
• Coolant leakage after servicing: Incorrect installation or disturbed seals may cause leakage following cooling system repairs.
• Repeated coolant loss under pressure: Small leaks may become more noticeable when the engine reaches operating temperature.
• Overheating during prolonged driving: Severe coolant loss may contribute to excessive engine temperatures.

Why Replacement Matters:
Replacing a defective coolant connection piece is important for maintaining the integrity of the engine cooling system.

A cracked, distorted or leaking adapter may allow coolant to escape, reducing the amount of coolant available to circulate through the engine.

Continued coolant loss can lead to overheating, particularly during demanding driving conditions or prolonged engine operation.

Excessive engine temperatures may damage seals, gaskets and other internal engine components.

Installing a Genuine Porsche replacement Coolant Connection Piece Adapter helps to:

• Restore a secure coolant connection: Replace a damaged or leaking connection piece.
• Prevent coolant leakage: Help maintain the correct seal between connected cooling system components.
• Maintain cooling system pressure: Support the intended operation of the pressurised cooling circuit.
• Preserve coolant circulation: Restore the correct passage between the associated coolant pipes.
• Support engine temperature control: Help maintain reliable cooling system operation.
• Reduce repeated coolant loss: Address leaks caused by a confirmed defective adapter.
• Reduce overheating risk: Repair a known coolant leak before significant fluid loss occurs.
• Restore correct pipe fitment: Maintain the specified connection geometry and component alignment.
• Support reliable engine operation: Help preserve cooling system performance during normal driving.
• Prevent further cooling system deterioration: Replace damaged components before leakage becomes more severe.
• Support engine refurbishment: Provide an original equipment component during cooling system or engine repairs.
• Preserve factory specifications: Maintain Porsche's intended coolant connection arrangement.
• Maintain Genuine Porsche quality: Use an original equipment replacement designed for the relevant engine.

Replacement is particularly recommended where inspection confirms cracking, damaged sealing surfaces, deformation, insecure attachment or persistent leakage originating from the adapter.

The associated seals, retaining components and connected coolant pipes should also be inspected during replacement.

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9A110613100

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Fits:
Porsche 997.2 Carrera 2009-12
Porsche 997.2 Turbo 2010-13
Porsche 991.1 Carrera 2012-16
Porsche 991.2 Carrera 2017-19
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>>

Click 'Zoom in' for large parts diagram.
Diagram ref no 1

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Fits:
Porsche 997.2 Carrera 2009-12
Porsche 997.2 Turbo 3.8L 2010-13

Click 'Zoom in' for large parts diagram.
Diagram ref no 23

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99710681230

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Coolant pipe seal. Pipe to Water Pump & Thermostat Housing.

Fits:
Porsche 987.2 Boxster 2009-12
Porsche 981 Boxster 2012-16
Porsche 981 Boxster Spyder 2016
Porsche 982 Boxster GTS 4.0 2019>>
Porsche 982 Boxster Spyder 2019>>
Porsche 987C Cayman 2009-12
Porsche 981C Cayman 2014-16
Porsche 981C Cayman GT4
Porsche 982C Cayman GTS 4.0L 2019>>
Porsche 982C Cayman GT4 2019>>
Porsche 997.2 Carrera 2009-12
Porsche 997.2 Turbo 2010-13
Porsche 991.1 Carrera 2012-16
Porsche 991.2 Carrera 2017-19
Porsche 991 Turbo 2014-20
Porsche 991 GT3 1014>>
Porsche 992.1 Carrera 2020>>
Porsche 992 Turbo 2020>>

Click 'Zoom in' for large parts diagram.
Diagram ref no 12

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0PB121437

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Coolant Supply Hose.

The Genuine Porsche Coolant Supply Hose 99710647772 is an original equipment replacement cooling system component designed for selected Porsche 911 (997) Turbo, GT2, GT2 RS, GT3 and GT3 RS models.

Fits:

• Porsche 997 MK1 TURBO 2007-09
• Porsche 997 MK1 GT3 / GT3 RS 2007-09
• Porsche 997 MK1 GT2 2007-09
• Porsche 997 MKII GT3 / GT3 RS 2010-11
• Porsche 997 MKII Turbo 2010-13
• Porsche 997 MKII GT2 RS 2011-13  

Diagram Ref No 32

Manufactured to Porsche's original specifications, this coolant hose connects the water pump housing to the coolant supply pipe, helping maintain reliable coolant circulation and effective engine temperature regulation.

The hose forms an essential part of the engine's liquid cooling system, providing a secure and flexible connection between cooling circuit components. It is designed to withstand the temperature changes, pressure fluctuations and vibration experienced during normal engine operation.

Over time, exposure to engine heat, coolant pressure and general ageing can cause the original hose to become hardened, swollen, cracked or weakened, potentially resulting in coolant leaks and reduced cooling system reliability.

The Genuine Porsche Coolant Supply Hose provides a direct original equipment replacement solution, helping restore the integrity of the cooling system while maintaining the correct hose routing and connection arrangement.

Ideal for routine cooling system maintenance, water pump repairs and engine refurbishment, this component helps protect the engine against coolant loss and overheating.

What This Product Does:
The coolant supply hose connects the engine's water pump housing to the coolant supply pipe, providing a sealed passage through which coolant circulates within the engine cooling system.

Its key functions include:

• Coolant Circulation: Allows coolant to flow between the water pump housing and the connected coolant supply pipe.
• Engine Temperature Regulation: Supports the cooling system's ability to maintain the engine within its intended operating temperature range.
• Secure Cooling System Connection: Provides a reliable connection between designated cooling system components.
• Leak Prevention: Helps maintain a sealed cooling circuit, reducing the risk of coolant escaping.
• Cooling System Pressure: Supports the integrity of the pressurised cooling system during normal operation.
• Thermal Resistance: Designed to withstand engine heat and repeated temperature fluctuations.
• Vibration Accommodation: Provides a flexible connection that accommodates normal engine vibration and movement.
• Overheating Prevention: Helps maintain sufficient coolant circulation to support effective engine cooling.
• Engine Protection: Reduces the risk of cooling-related damage by maintaining a dependable coolant flow path.
• Original Equipment Fitment: Maintains Porsche's specified hose dimensions, routing and connection arrangement.

Symptoms Of Wear Or Failure:
Over time, continuous exposure to engine heat, coolant pressure, vibration and ageing can cause coolant supply hoses to deteriorate.

Common signs include:

• Visible Coolant Leaks: Coolant dripping beneath the vehicle or collecting around the water pump housing may indicate a damaged or leaking hose.
• Low Coolant Warning: Coolant escaping from a worn hose may cause the reservoir level to fall, triggering a dashboard warning.
• Frequent Coolant Top-Ups: Repeatedly needing to refill the coolant reservoir may indicate a leak within the cooling system.
• Cracked or Split Hose Material: Visible cracks, splits or surface deterioration may indicate ageing or weakening of the hose.
• Swollen or Bulging Hose: Internal deterioration or abnormal cooling system pressure may cause the hose to expand or deform.
• Hardened or Brittle Rubber: Repeated exposure to high temperatures may reduce flexibility and increase the risk of cracking.
• Soft or Spongy Sections: Localised weakening of the hose structure can indicate internal deterioration.
• Coolant Residue Around Connections: Dried coolant deposits or staining around the hose ends may indicate previous or ongoing leakage.
• Coolant Smell from the Engine Bay: Escaping coolant may produce a distinctive sweet smell, particularly when contacting warm engine components.
• Engine Overheating: Significant coolant loss can reduce the cooling system's ability to regulate engine temperature.
• Fluctuating Engine Temperature: Coolant loss or air entering the cooling system may contribute to unstable temperature readings.
• Steam from the Engine Compartment: A severe coolant leak may allow coolant to contact hot engine components, producing visible steam.
• Loose or Damaged Hose Connections: Deteriorated clamps or damaged connection surfaces may allow coolant to escape.

Why Replacement Matters:

• Replacing a worn, leaking or damaged coolant supply hose is essential for maintaining the reliability, performance and long-term protection of your Porsche's engine cooling system.
• The engine cooling system relies on the continuous circulation of coolant through a sealed network of hoses, pipes and associated components. The coolant supply hose plays an important role by maintaining a secure connection between the water pump housing and the coolant supply pipe.
• As the original hose ages, repeated heating and cooling cycles can cause the material to lose flexibility, develop cracks or weaken around its connection points.
• Even a small coolant leak can gradually reduce the coolant level, limiting the system's ability to control engine temperature effectively.
• If the hose deteriorates further or fails suddenly under pressure, rapid coolant loss may occur, potentially resulting in engine overheating and an unexpected breakdown.
• Overheating can cause serious damage to internal engine components, including cylinder heads, gaskets and associated cooling system parts.
• A correctly fitted Genuine Porsche replacement hose helps restore the original cooling system connection, ensuring appropriate fitment, routing and sealing performance.
• Maintaining reliable engine cooling is particularly important for high-performance Porsche Turbo, GT2 and GT3 models, where the engine can experience substantial thermal loads during demanding driving conditions.
• Replacing deteriorated hoses during water pump servicing or major cooling system maintenance can also help prevent recurring leaks and reduce the likelihood of more expensive repairs.
• The genuine replacement maintains the original equipment configuration, making it suitable for Porsche owners who wish to preserve factory-standard component quality and fitment.

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99710647772

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Coolant Supply Hose.

The Porsche Coolant Supply Hose 9A110666001 is a genuine Porsche replacement water hose used within the engine cooling system on selected Porsche 997-generation 911 models.

Fits:

• Porsche 997 MKII Carrera C2 3.6L 2009-12
• Porsche 997 MKII Carrera C4 3.6L 2009-12
• Porsche 997 MKII Carrera C2S 3.8L 2009-12
• Porsche 997 MKII Carrera C4S 3.8L 2009-12
• Porsche 997 MKII Turbo 2010-13
• Porsche 997 MKII GT2 RS 2011-13  

Diagram Ref No 15

The hose forms part of the engine-side coolant pipework and carries pressurised coolant through the water-pipe assembly, helping maintain stable engine temperature under normal driving and high-load operating conditions.

What This Product Does:
The engine cooling system circulates coolant through the engine, radiators, thermostat and associated pipes to remove excess heat.

The coolant supply hose forms part of this sealed, pressurised circuit.

Its functions include:

• Carrying engine coolant through the cooling system
• Maintaining consistent coolant circulation
• Supporting stable engine operating temperature
• Connecting associated water-pipe and engine cooling components
• Containing coolant under pressure
• Helping prevent coolant loss
• Supporting correct thermostat and water-pump operation
• Maintaining the factory Porsche cooling-system layout

Although relatively small, a sound supply hose is essential for keeping the cooling circuit sealed and dependable.

Symptoms Of Wear Or Failure:
Coolant hoses deteriorate over time through heat, pressure, vibration and chemical exposure.

Possible signs of failure include:

• Visible coolant leakage
• Pink, white or coloured coolant residue around the hose
• Dampness around hose connections
• Cracks in the hose surface
• Splitting around the ends
• Swollen or bulging hose sections
• Hose becoming unusually soft
• Hose becoming hard or brittle
• Coolant smell around the engine
• Falling coolant level
• Frequent need to top up coolant
• Low-coolant warning
• Engine-temperature fluctuations
• Engine overheating
• Steam from the engine area

A hose may also deteriorate internally without severe external cracking, so condition should be assessed carefully during cooling-system maintenance.

Why Replacement Matters:
A deteriorated coolant hose can eventually leak or rupture.

Because the cooling system operates under pressure, even a small split can lead to rapid coolant loss once the engine reaches operating temperature.

Continued driving with a failed hose may result in:

• Loss of cooling-system pressure
• Reduced coolant circulation
• Engine overheating
• Turbocharger heat-management problems
• Damage to seals and gaskets
• Cylinder-head damage
• Severe engine damage in extreme cases
• Vehicle breakdown

Replacing an aged or leaking hose restores the integrity of the cooling circuit and reduces the risk of sudden coolant loss.

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Fits:
Porsche 997 MKI Carrera All.
997 Carrera 2 3.6L 2005>>
997 Carrera 2S 3.8L 2005>>
997 Carrera 4 3.6L 2005>>
997 Carrera 4S 3.8L 2005>>
Porsche 997 MKI Turbo

Porsche 997 MKII Carrera All. 2009>>
997 Carrera 2 3.6L 2009>>
997 Carrera 2S 3.8L 2009>>
997 Carrera 4 3.6L 2009>>
997 Carrera 4S 3.8L 2009>>
Porsche 997 MKII Turbo 2009>>

Diagram Ref no 7

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Fits:
Porsche 981 Boxster 2012>>2016
Porsche 981 Cayman 2014>>2016
Porsche 981 Boxster Spyder 2016>>2016
Porsche 982 Boxster GTS (718) 4.0L 2017>>
Porsche 982 Cayman GTS (718) 4.0L 2017>>
Porsche 982 Boxster Spyder (718) 2019>>
Porsche 987.2 Boxster MKII 2009>>2012
Porsche 987.2 Cayman MKII 2009>>2012
Porsche 991.1 Carrera MKI 2012>>2016
Porsche 991.2 Carrera MKII 2017>>2019
Porsche 991 Turbo / Turbo S / GT2 RS MKI / MKII 2014>>2020
Porsche 992.1 Carrera MKI 2019>>2024
Porsche 992.2 Carrera 2 3.0L MKII 2024>>
Porsche 992.1 Turbo / Turbo S MKI 2020>>
Porsche 997.2 Carrera MKII 2009>>2012
Porsche 997.2 Turbo / GT2 RS MKII 2010>>2013
Porsche 981 Cayman GT4 2016>>2016
Porsche 982 Cayman GT4 (718) 2019>>

Diagram Ref No 16

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Fits:
Porsche 997.2 Carrera 2009 - 2012
Porsche 997.2 Turbo 3.8L 2010 - 2013 (A170)

Diagram ref no 22

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99710682232

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Engine coolant supply hose
Engine coolant supply hose by Porsche for the specified 997.2 Carrera and Turbo models. The supplied cooling diagrams identify this component as a supply hose within the engine coolant circuit.

Fits

• Porsche 997.2 Carrera C2 3.6L 2009 – 2012
• Porsche 997.2 Carrera C4 3.6L  2009 – 2012
• Porsche 997.2 Carrera C2S 3.8L  2009 – 2012
• Porsche 997.2 Carrera C4S 3.8L  2009 – 2012
• Porsche 997.2 Turbo 2010 – 2013

Diagram ref no 1

What This Product Does

This hose carries coolant along the engine's supply circuit. It forms part of the fluid pathway used by the cooling system to manage engine temperature; it is not the return hose or a coolant pipe shown elsewhere in the assembly.

Functions

• Provides a passage for coolant on the supply side.
• Connects components within the engine cooling circuit.
• Supports coolant movement needed for temperature regulation.

Technical Details

• Porsche part number: 99710683131.
• Component type: engine water/coolant hose.
• Diagram identification: supply.

Symptoms of Fault

• Falling coolant level or repeated coolant-level warnings.
• Sweet-smelling coolant around the engine compartment.
• Moisture, staining or dried deposits at hose connections.
• Cracks, swelling or unusually soft areas in the hose.
• Leakage becoming apparent after the engine is switched off.
• Rising temperature readings, steam or gurgling.

These signs can also originate from other cooling components, so confirm the leak source before replacing the hose.

Why Replacement Matters

Age, repeated heating and cooling, and deterioration at connections can leave a hose unable to retain coolant. Renewing a confirmed damaged hose addresses that leakage and helps restore the coolant pathway. Inspect associated clamps, fittings and neighbouring hoses during the repair rather than assuming the hose alone explains every symptom.

FAQs

Why might leakage appear only when hot?
Changes in temperature and system pressure can reveal deterioration that is not apparent when cold.

How should a suspected leak be located?
A cooling-system pressure test, followed by inspection of hose ends and nearby fittings, can help identify its source.

Could gurgling indicate a hose problem?
Air entering through a leak or a low coolant level can cause gurgling, but the sound does not identify this hose specifically.

Should other components be checked?
Yes. Examine the clamps, connectors and surrounding cooling components for deterioration or additional leakage.

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99710683131

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Heater hose - Engine to return line.
Genuine Porsche Original Equipment (OE) heater coolant return hose that connects between the engine cooling circuit and the heater return line, ensuring proper coolant flow through the heater core and back to the engine cooling system.

Fits:
Porsche 996 Carrera 2002 - 2005 Tiptronic Gearbox only
Porsche 997.1 3.6L / 3.8L 2004 - 2008
Porsche 997.1 Turbo / GT2 2007 - 2009
Porsche 997.2 Turbo / GT2 RS 2010 - 2013
Porsche 997 GT3 3.8 / 4.0 2009 - 2011

Diagram ref no 42

This hose ensures an unobstructed and secure channel for coolant returning from the vehicle’s heater core to the engine cooling loop, playing a vital role in passenger cabin heating and overall engine thermal regulation. Its precise fit and correct routing are essential to avoid bypassing or pinching, which could otherwise lead to heater inefficiency or premature failure.

Installed between the heater core outlet and the engine’s return fitting, this hose:
• Transports heated coolant from the heater core back to the engine cooling system
• Maintains correct flow and pressure balance within the cooling circuit
• Operates under high temperatures and multiple thermal cycles
•  Interfaces with factory-specified clamps and hose connections
Because it is made to OE specification, the hose ensures proper sealing and routing that matches the original Porsche design.

A cooling system hose that has become brittle, cracked, swollen, or porous can leak or restrict flow, leading to reduced heating performance, coolant loss, and potential engine overheating. Because the heater return hose carries pressurised coolant across temperature extremes, degradation over time is typical. Replacing it with a Genuine Porsche OE part ensures correct material performance and sealing, helping preserve cooling efficiency and prevent unexpected failures.

When to replace:
•  Visible cracks, swelling, or soft spots
•  Coolant leaks around the hose ends
•  Heater blowing cold air, indicating poor coolant flow
•  Cooling system overhaul or heater core service
•  Preventive maintenance on high-mile vehicles

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Heater hose - Engine to return line.
OE Match heater coolant return hose is a direct-fit replacement designed to replicate the original Porsche hose used in the heater return circuit on Porsche 911 996 and 997 models. It carries coolant from the heater core back into the engine cooling system, supporting both cabin heating and overall thermal regulation.

Fits:
Porsche 996 Carrera 2002 - 2005 Tiptronic Gearbox only
Porsche 997.1 3.6L / 3.8L 2004 - 2008
Porsche 997.1 Turbo / GT2 2007 - 2009
Porsche 997.2 Turbo / GT2 RS 2010 - 2013
Porsche 997 GT3 3.8 / 4.0 2009 - 2011

Diagram ref no 42

The hose installs directly using original mounting points and standard Porsche hose clamps, making it suitable for both routine maintenance and larger cooling system overhauls.

The heater coolant return hose channels warmed coolant from the heater core back to the engine’s cooling circuit, completing the heater loop. This allows the cooling system to maintain balanced flow and ensures consistent interior heating performance.

Installed between the heater core outlet and the engine return line, this hose:
•  Maintains correct coolant flow and pressure in the heater circuit
•  Supports reliable cabin heating
•  Resists collapse, swelling, and heat degradation
•  Integrates with factory hose routing and connections
 Its OE-matched geometry ensures proper clearance and reduces stress on joints and adjacent hoses.

Over time, heater hoses deteriorate due to heat cycling and coolant exposure. A failing return hose can cause coolant leaks, reduced heating efficiency, air ingress into the cooling system, or engine overheating. Replacing worn hoses with an OE Match component restores proper coolant circulation and helps prevent unexpected cooling system failures.

When to replace:
•  Visible cracks, swelling, or soft spots
•  Coolant leaks around the hose ends
•  Heater blowing cold air, indicating poor coolant flow
•  Cooling system overhaul or heater core service
•  Preventive maintenance on high-mile vehicles

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Fits:
Porsche 987 Boxster 2005-12
Porsche 987 Cayman 2006-12

Porsche 981 Boxster 2012-16 
Porsche 981 Boxster Spyder 2016 
Porsche 981 Cayman 2014-16 
Porsche 981 Cayman GT4 2016 

Porsche 718 (982) Boxster 2017>> 
Porsche 718 (982) Boxster Spyder 2019>>
Porsche 718 (982) Cayman 2017>>
Porsche 718 (982) Cayman GT4 2019>>

Porsche 996 GT3 / RS 1999-05
Porsche 996 Turbo / GT2 2001-05

Porsche 997 Carrera 2005-12
Porsche 997 Turbo / GT2 RS 2007-13
Porsche 997 GT3 / RS 2007-11

Porsche 991 Carrera 2012-19
Porsche 991 Turbo / GT2 RS 2014-20
Porsche 991 GT3 / RS 2014-21

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99610680103

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O-ring – 46.7 x 3.53 – used in various applications within the car's cooling system.

Fits:
Porsche 987 Boxster 2005-12
Porsche 987 Cayman 2006-12

Porsche 981 Boxster 2012-16 
Porsche 981 Boxster Spyder 2016 
Porsche 981 Cayman 2014-16 
Porsche 981 Cayman GT4 2016 

Porsche 718 (982) Boxster 2017>> 
Porsche 718 (982) Boxster Spyder 2019>>
Porsche 718 (982) Cayman 2017>>
Porsche 718 (982) Cayman GT4 2019>>

Porsche 996 GT3 / RS 1999-05
Porsche 996 Turbo / GT2 2001-05

Porsche 997 Carrera 2005-12
Porsche 997 Turbo / GT2 RS 2007-13
Porsche 997 GT3 / RS 2007-11

Porsche 991 Carrera 2012-19
Porsche 991 Turbo / GT2 RS 2014-20
Porsche 991 GT3 / RS 2014-21

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Fits:
Porsche 996 Turbo / GT2 2001>>2005
Porsche 996 GT3 1999>>2005
Porsche 997.1 Turbo / GT2 MKI 2007>>2009
Porsche 997.1 GT3 MKI 2007>>2009
Porsche 997.2 Turbo / GT2 RS MKII 2010>>2013
Porsche 997.2 GT3 MKII 2010>>2011

Diagram Ref No 16

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