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Coolant return hose. Porsche 997.1 Carrera 2005-08 - 99710683204
99710683204
Vehicle Group
- Porsche 997 MK1 Carrera 2 3.6L 2005-08
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
Information
Coolant Return Hose, Return hose at the thermostat housing.
This original Porsche coolant hose forms part of the engine cooling system, helping return coolant through the cooling circuit and maintain correct engine operating temperature.
Fits:
Porsche 997.1 C2 / C2S 2005 - 2008
Porsche 997.1 C4 / C4S 2005 - 2008
Diagram ref no 15
This hose is used in the water pump / thermostat housing area on selected Porsche 997.1 models.
What This Part Does / Functions:
• Routes coolant through the return side of the cooling system
• Connects at the thermostat housing area where specified
• Helps maintain correct coolant circulation and engine temperature control
• Supports proper cooling system pressure and flow
• Replaces a cracked, swollen, leaking or heat-damaged original hose
• Helps prevent coolant loss and overheating risk
• Provides correct Genuine Porsche hose shape, material and connection fitment
• Supports reliable factory cooling system performance.
Why Replace This Part?
Coolant hoses are exposed to heat cycles, coolant pressure, engine bay temperatures, vibration and age-related rubber deterioration. Over time, the hose can harden, swell, crack, split or leak. A failing coolant return hose may cause coolant loss, low coolant warnings, overheating risk or visible coolant residue around the thermostat housing.
Replacing it with a Genuine Porsche coolant return hose helps restore the correct factory coolant routing and reliable cooling system sealing.
Common Symptoms of a Faulty Coolant Return Hose
• Coolant leak around the thermostat housing
• Dried coolant residue around the hose connections
• Low coolant warning
• Coolant smell from the rear engine bay
• Engine temperature rising above normal
• Hose swelling, cracking or softening
• Cooling system pressure loss
• Damage found during cooling system inspection.
When to Replace This Part
• If the original hose is cracked, swollen, leaking or damaged
• During thermostat housing or water pump service
• During cooling system overhaul
• When replacing related coolant pipes, hoses or clamps
• If coolant loss is traced to the return hose
• After engine bay service where the hose has been disturbed
• If the hose has become brittle, soft or oil-contaminated
Where It Fits on the Car
This hose fits in the engine cooling / water cooling system at the thermostat housing area. It is identified as the coolant return hose / water hose return line and is shown in Porsche cooling diagrams as diagram reference no. 15.
Correct routing, clamp positioning and sealing are important to prevent coolant leaks and maintain proper cooling system operation.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710683204
The product you are viewing cross references to these numbers
This original Porsche coolant hose forms part of the engine cooling system, helping return coolant through the cooling circuit and maintain correct engine operating temperature.
Fits:
Porsche 997.1 C2 / C2S 2005 - 2008
Porsche 997.1 C4 / C4S 2005 - 2008
Diagram ref no 15
This hose is used in the water pump / thermostat housing area on selected Porsche 997.1 models.
What This Part Does / Functions:
• Routes coolant through the return side of the cooling system
• Connects at the thermostat housing area where specified
• Helps maintain correct coolant circulation and engine temperature control
• Supports proper cooling system pressure and flow
• Replaces a cracked, swollen, leaking or heat-damaged original hose
• Helps prevent coolant loss and overheating risk
• Provides correct Genuine Porsche hose shape, material and connection fitment
• Supports reliable factory cooling system performance.
Why Replace This Part?
Coolant hoses are exposed to heat cycles, coolant pressure, engine bay temperatures, vibration and age-related rubber deterioration. Over time, the hose can harden, swell, crack, split or leak. A failing coolant return hose may cause coolant loss, low coolant warnings, overheating risk or visible coolant residue around the thermostat housing.
Replacing it with a Genuine Porsche coolant return hose helps restore the correct factory coolant routing and reliable cooling system sealing.
Common Symptoms of a Faulty Coolant Return Hose
• Coolant leak around the thermostat housing
• Dried coolant residue around the hose connections
• Low coolant warning
• Coolant smell from the rear engine bay
• Engine temperature rising above normal
• Hose swelling, cracking or softening
• Cooling system pressure loss
• Damage found during cooling system inspection.
When to Replace This Part
• If the original hose is cracked, swollen, leaking or damaged
• During thermostat housing or water pump service
• During cooling system overhaul
• When replacing related coolant pipes, hoses or clamps
• If coolant loss is traced to the return hose
• After engine bay service where the hose has been disturbed
• If the hose has become brittle, soft or oil-contaminated
Where It Fits on the Car
This hose fits in the engine cooling / water cooling system at the thermostat housing area. It is identified as the coolant return hose / water hose return line and is shown in Porsche cooling diagrams as diagram reference no. 15.
Correct routing, clamp positioning and sealing are important to prevent coolant leaks and maintain proper cooling system operation.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710683204
99710683204
99710683203
The product you are viewing cross references to these numbers
Price: £70.07
In stock
Related products
Vehicle Group
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche 996 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>
- Porsche 996 GT3 RS 2003-04
- 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 Carrera GT 2003-06
Information
O-ring 39,20 x 3,00 water cooling.
Fits:
Porsche 996 turbo - 2000 to 2005
Porsche 996 GT3 - 1999 to 2004
Porsche 997.1 turbo - 2007 to 2009
Porsche 997 GT3 - 2007 to 2011
Porsche Carrera GT - 2003 to 2006
Porsche 918 Spyder
Diagram ref no 14
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99970741040
The product you are viewing cross references to these numbers
Fits:
Porsche 996 turbo - 2000 to 2005
Porsche 996 GT3 - 1999 to 2004
Porsche 997.1 turbo - 2007 to 2009
Porsche 997 GT3 - 2007 to 2011
Porsche Carrera GT - 2003 to 2006
Porsche 918 Spyder
Diagram ref no 14
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99970741040
99970741040
The product you are viewing cross references to these numbers
Price: £8.40
In stock
Vehicle Group
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche 996 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>
- Porsche 996 GT3 RS 2003-04
- 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 Carrera GT 2003-06
Information
O-ring 39,20 x 3,00 water cooling
This OE match O-ring is a direct replacement for the original Porsche sealing ring used within the water cooling systems of Porsche 996 Turbo, 996 GT3, 997 Turbo, and 997 GT3 models. Manufactured to OE specifications, it features precise dimensions of 39.20mm x 3.00mm to ensure correct sealing performance and factory-style fitment.
Sold individually
Fits:
Porsche 996 turbo - 2000 to 2005
Porsche 996 GT3 - 1999 to 2004
Porsche 997.1 turbo - 2007 to 2009
Porsche 997 GT3 - 2007 to 2011
Porsche Carrera GT - 2003 to 2006
Porsche 918 Spyder
Diagram ref no 14
Proper sealing within the cooling system is essential for maintaining coolant pressure and preventing leaks that could lead to overheating or engine damage. OE Match construction ensures compatibility with original Porsche cooling system components and reliable sealing performance under demanding operating conditions.
Ideal for preventative maintenance, cooling system servicing, or engine rebuild work, this O-ring helps restore proper sealing integrity and reliable coolant circulation.
The O-ring creates a pressure-tight seal between cooling system components, preventing coolant leaks and maintaining correct cooling system pressure. It helps ensure efficient coolant circulation and reliable engine temperature control.
Function
• Seals coolant system connections and housings
• Prevents coolant leakage under pressure
• Maintains correct cooling system pressure
• Supports reliable engine temperature regulation
• Resists heat, coolant exposure, and pressure cycling
Cooling system O-rings harden and lose elasticity over time due to heat exposure, coolant chemicals, and pressure cycling. A deteriorated seal can cause coolant leaks, pressure loss, overheating, and potential engine damage. Replacing worn O-rings during servicing helps maintain cooling system integrity and prevents costly repairs.
When to replace
• Coolant leaks around sealed connections
• During cooling system disassembly or servicing
• Signs of flattened, cracked, or hardened seals
• Loss of coolant pressure
• During engine rebuild or preventative maintenance
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99970741040
The product you are viewing cross references to these numbers
This OE match O-ring is a direct replacement for the original Porsche sealing ring used within the water cooling systems of Porsche 996 Turbo, 996 GT3, 997 Turbo, and 997 GT3 models. Manufactured to OE specifications, it features precise dimensions of 39.20mm x 3.00mm to ensure correct sealing performance and factory-style fitment.
Sold individually
Fits:
Porsche 996 turbo - 2000 to 2005
Porsche 996 GT3 - 1999 to 2004
Porsche 997.1 turbo - 2007 to 2009
Porsche 997 GT3 - 2007 to 2011
Porsche Carrera GT - 2003 to 2006
Porsche 918 Spyder
Diagram ref no 14
Proper sealing within the cooling system is essential for maintaining coolant pressure and preventing leaks that could lead to overheating or engine damage. OE Match construction ensures compatibility with original Porsche cooling system components and reliable sealing performance under demanding operating conditions.
Ideal for preventative maintenance, cooling system servicing, or engine rebuild work, this O-ring helps restore proper sealing integrity and reliable coolant circulation.
The O-ring creates a pressure-tight seal between cooling system components, preventing coolant leaks and maintaining correct cooling system pressure. It helps ensure efficient coolant circulation and reliable engine temperature control.
Function
• Seals coolant system connections and housings
• Prevents coolant leakage under pressure
• Maintains correct cooling system pressure
• Supports reliable engine temperature regulation
• Resists heat, coolant exposure, and pressure cycling
Cooling system O-rings harden and lose elasticity over time due to heat exposure, coolant chemicals, and pressure cycling. A deteriorated seal can cause coolant leaks, pressure loss, overheating, and potential engine damage. Replacing worn O-rings during servicing helps maintain cooling system integrity and prevents costly repairs.
When to replace
• Coolant leaks around sealed connections
• During cooling system disassembly or servicing
• Signs of flattened, cracked, or hardened seals
• Loss of coolant pressure
• During engine rebuild or preventative maintenance
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99970741040
99970741040
The product you are viewing cross references to these numbers
Price: £6.49
In stock