Water radiator bottom hose LEFT. Porsche 996 C2/C4/ 986 S 3.2L  ❭  99610662558

Water radiator bottom hose, LEFT.
This hose serves as the lower radiator return hose (left side) in the engine cooling system of the Porsche 996 Carrera / Carrera 4 and 986 Boxster S 3.2L.  It replaces older hose numbers such as 99610662554 and 99610662557, offering a faithful reproduction of the original hose in terms of shape, diameter, and fitment.

Fits:
Porsche 996 C2 / C4 1998 - 2005
Porsche 986 Boxster S 3.2L 1997 - 2004

Diagram Ref No 9.

The radiator coolant hose circulates engine coolant between the radiator and engine blocks or cooling passages. As a key part of the cooling system, it helps transfer heated fluid away from the engine and into the radiator to be cooled, then back into the engine - maintaining stable operating temperatures and preventing overheating under normal driving conditions. A robust and properly functioning coolant hose ensures efficient heat dissipation and preserves engine performance.

Function:
• Transfers coolant between the radiator and engine cooling system
• Helps maintain optimal engine temperatures
• Reduces the risk of overheating and coolant leaks
• Made from heat- and fluid-resistant materials to endure typical engine bay conditions

Radiator hoses are constantly exposed to engine heat, pressure cycles, and coolant chemicals. Over time, hoses can dry out, crack, soften, or swell, leading to leaks or cooling system failure. A compromised hose can quickly result in engine overheating, potential head gasket damage, and costly repairs. Replacing a worn or aged hose restores secure coolant flow, enhances system integrity, and helps maintain original-style engine temperature management.

Replace this radiator hose if:
• The hose shows cracks, swelling, or brittleness
• Coolant is visible leaking around hose connections or surface
• The hose feels soft or mushy under pressure
• You notice engine overheating or rapid temperature fluctuations
• Routine cooling system maintenance or belt/thermostat replacement

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99610662558

The product you are viewing cross references to these numbers