Coolant Hoses - Engine Bay

Coolant return pipe.



Fits:
Porsche 997.1 Turbo 3.6L / GT2 2007-09
Porsche 997.2 GT2 RS 3.6L 2010-13

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Diagram ref no 4

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99710625474

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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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9A110666001

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Coolant supply line for the turbocharger. 

Fits:
Porsche 997-1 Turbo / GT2 2007-09 
Porsche 997-2 GT2 RS 2011-13

Diagram reference(s):

No. 11 - Cylinders 1-3
No. 12 - Cylinders 4-6

NOTE: Our product image shows 99710607379, which is for cylinders 1-3.

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99710607

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Coolant water return tube.



Fits:
Porsche 997.2 GT2 RS 2010-13

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Diagram ref no 8

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99710606901

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Engine Coolant Inlet Flange Drain Plug.
Sold Each.
x3 Required Per Car.

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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0PB121099

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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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99610622275

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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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99610622275

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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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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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99610680103

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Protective Ring For Engine Coolant Pipe.
Sold Each.
x2 Required Per Car.

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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99610621470

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Regulating valve water cooling. 



Fits:
Porsche 981 Boxster - 2012 to 2016
Porsche 981 Cayman - 2013 to 2016
Porsche 718 Boxster - 2017 Onwards
Porsche 718 Cayman - 2017 Onwards
Porsche 997.2 - 2009 to 2012
Porsche 991 - 2012 to 2019

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Diagram ref no 4


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Regulating Valve Water Cooling.
This Regulating Valve Water Cooling is a OE MATCH Porsche component designed to control and regulate coolant flow within the engine’s water cooling system. Acting as a precision valve within the cooling circuit, it ensures that coolant is directed appropriately to maintain optimal engine operating temperatures under varying conditions.

Fits:

• Porsche Boxster 981 2.7L 2012-16
• Porsche Boxster 981 S / GTS 3.4L 2012-16
• Porsche Boxster 981 Spyder 3.8L 2016
• Porsche Boxster 718 2.0L Manual (300 Bhp) 2017>>
• Porsche Boxster 718 2.0L PDK (300 Bhp) 2017>>
• Porsche Boxster S 718 2.5L Manual (350 Bhp) 05/2017>>
• Porsche Boxster S 718 2.5L PDK (350 Bhp) 05/2017>>
• Porsche Boxster T 718 2.0L Manual (300 Bhp) 01/2019>>
• Porsche Boxster T 718 2.0L PDK (300 Bhp) 01/2019>>
• Porsche Boxster GTS 718 2.5L Manual (365 Bhp) 05/2017>>
• Porsche Boxster GTS 718 2.5L PDK (365 Bhp) 05/2017>>
• Porsche Boxster GTS 718 4.0L Manual (400 Bhp) 01/2019>>
• Porsche Boxster GTS 718 4.0L PDK (400 Bhp) 01/2019>>
• Porsche Boxster Spyder / Sypder RS 718 4.0L 01/2019>>
• Porsche Boxster 25 Years 718 4.0L Manual (400 Bhp) 01/2020>>
• Porsche Boxster 25 Years 718 4.0L PDK (400 Bhp) 01/2020>>
• 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 GT3 2010-11
• Porsche 997 MKII Turbo 2010-13
• Porsche 997 MKII GT2 RS 2011-13
• Porsche 991.1 Carrera C2 3.4L (350 Bhp) 2012-16
• Porsche 991.1 Carrera C2S / GTS 3.8L (400/430 Bhp) 2012-16
• Porsche 991.1 Carrera C4 3.4L (350 Bhp) 2012-16
• Porsche 991.1 Carrera C4S / GTS 3.8L (400/430 Bhp) 2012-16
• Porsche 991.1 Turbo 3.8L (520 Bhp) 2014-16
• Porsche 991.1 Turbo S 3.8L (560 Bhp) 2014-16
• Porsche 991.1 R 4.0L (500 Bhp) 2016
• Porsche 991.1 GT3 3.8L (475 Bhp) 2014-16
• Porsche 991.1 GT3 RS 4.0L (500 Bhp) 2015-16
• Porsche 991.2 Carrera 2 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Carrera 2S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Carrera 4 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Carrera 4S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Cabriolet 2 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Cabriolet 2S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Cabriolet 4 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Cabriolet 4S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Targa 4 3.0L (370 Bhp) 2016-19
• Porsche 991.2 Targa 4S / GTS 3.0L (420/450 Bhp) 2016-19
• Porsche 991.2 Turbo Coupe 3.8L (540 Bhp) 2016-19
• Porsche 991.2 Turbo S Coupe 3.8L (580 Bhp) 2016-19
• Porsche 991.2 Turbo Cabriolet 3.8L (540 Bhp) 2016-19
• Porsche 991.2 Turbo S Cabriolet 3.8L (580 Bhp) 2016-19
• Porsche 991.2 Speedster 4.0L (510Bhp) 2019
• Porsche 991.2 GT3 4.0L (500 Bhp) / GT3 RS 4.0L (520 Bhp) 2017-19
• Porsche 991.2 GT2 RS 3.8L PDK (700 bhp) 2018-19
• Porsche Cayman 2.7L 981 2013-16
• Porsche Cayman S / GTS 3.4L 981 2013-16
• Porsche Cayman GT4 3.8L 2015-16
• Porsche Cayman 718 2.0L Manual (300 Bhp)
• Porsche Cayman 718 2.0L PDK (300 Bhp)
• Porsche Cayman S 718 2.5L Manual (350 Bhp)
• Porsche Cayman S 718 2.5L PDK (350 Bhp)
• Porsche Cayman T 718 2.0L Manual (300 Bhp)
• Porsche Cayman T 718 2.0L PDK (300 Bhp)
• Porsche Cayman GTS 718 2.5L Manual (365 Bhp)
• Porsche Cayman GTS 718 2.5L PDK (365 Bhp)
• Porsche Cayman GTS 718 4.0L Manual (400 Bhp)
• Porsche Cayman GTS 718 4.0L PDK (400 Bhp)
• Porsche Cayman GT4 718 4.0L / GT4 RS 718 4.0L  
  
  

Diagram Ref No 4

What This Product Does:

• Regulates coolant flow within the engine cooling system
• Maintains optimal engine temperature under all driving conditions
• Directs coolant to different circuits as required
• Supports efficient engine warm-up and cooling
• Works with thermostats and other cooling components to balance system performance     

Symptoms Of Wear Or Failure:

• Engine overheating or temperature fluctuations
• Engine running too cool (inefficient operation)
• Coolant leaks around the valve housing
• Poor heater performance or inconsistent cabin temperature
• Check engine light related to cooling system faults
• Reduced engine efficiency due to improper temperature control  

Why Replacement Matters:

• Restores proper coolant flow and temperature control
• Prevents overheating and potential engine damage
• Ensures optimal engine efficiency and fuel economy
• Protects cooling system components from excessive stress
• Maintains reliable operation of both engine and heating systems  

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9P1317233

The product you are viewing cross references to these numbers

Water coolant hose return. 



Fits:
Porsche 997.1 turbo - 2007 to 2008
Porsche 997.2 GT2 - 2001 to 2012
Porsche 997 GT3 - 2007 to 2012

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Diagram ref no 2 or 45

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99710632872

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Water coolant hose, supply.



Fits:
Porsche 997.1
Porsche 997.2

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Diagram ref no 17

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99710674006

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Water Coolant Pipe, Supply.

Fits:
Porsche 997.1 2005-08
Porsche 997.2 2009-12

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Diagram ref no 1

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99710661032

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Water Hose Supply. 

The Porsche Water Hose Supply 99710650101 is a genuine replacement coolant supply hose designed for selected Porsche 997 performance 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 9

Located on the right-hand side of the engine cooling circuit, the hose carries coolant from the supply pipe towards the engine, helping maintain continuous coolant circulation and stable operating temperatures.

Manufactured to Porsche specifications, this replacement restores the original hose routing, connections and sealing arrangement when the existing hose has become cracked, hardened, swollen or is leaking.

What This Product Does:
The engine cooling system continuously circulates coolant through the engine, radiators and associated pipework to absorb and dissipate heat.

This supply hose forms part of that circulation path and delivers coolant from the supply pipe into the engine cooling circuit.

Its main functions include:

• Carrying coolant towards the engine
• Maintaining continuous coolant circulation
• Helping maintain correct cooling-system pressure
• Supporting stable engine operating temperatures
• Providing a sealed connection between the coolant pipe and engine
• Helping prevent coolant loss
• Maintaining the original factory hose routing
• Supporting effective engine thermal management

The hose itself does not lower coolant temperature, but reliable coolant flow through it is essential for the cooling system to function correctly.

Symptoms Of Wear Or Failure:
Coolant hoses operate under continuous heat and pressure and can deteriorate as they age.

Common symptoms of a worn or failing coolant supply hose include:

• Visible coolant leakage
• Dampness around the hose or fittings
• Dried coolant residue around connection points
• Cracks or splits in the hose
• Rubber becoming hard or brittle
• Swelling or bulging sections
• Hose becoming excessively soft or spongy
• Damaged or loose hose connections
• Low coolant warning
• Repeated need to top up coolant
• Sweet coolant smell around the engine bay
• Engine temperature rising above normal
• Fluctuating coolant temperature
• Steam from the engine compartment in severe cases

Cooling-system leaks can also originate from radiators, expansion tanks, water pumps, pipe connections or other hoses, so the complete circuit should be inspected.

Why Replacement Matters:
The cooling system must remain sealed and properly pressurised to control engine temperature effectively.

If the supply hose begins to leak, coolant can escape and the system may gradually lose both fluid and pressure. As the coolant level falls, the engine becomes less able to transfer and dissipate heat.

A deteriorated hose may also split suddenly under operating pressure, causing rapid coolant loss.

Continued operation with insufficient coolant can lead to:

• Engine overheating
• Cylinder-head damage
• Head-gasket damage
• Damage to seals and cooling-system components
• Reduced engine reliability
• Breakdown caused by sudden coolant loss

Replacing a deteriorated hose helps restore:

• Correct coolant circulation
• Proper cooling-system pressure
• A sealed cooling circuit
• Stable engine temperature
• Reliable long-term cooling-system operation

Replacing a hose at the first sign of leakage, cracking or swelling can help prevent a relatively minor cooling-system fault from becoming a much more expensive engine repair.

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99710650101

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