Coolant return water hose. Porsche 996 1998-01 3.4L C2 MANUAL  ❭  99610664162

Coolant return water hose
This OE Match coolant return water hose is a cooling system hose designed for Porsche 911 (996) Carrera 3.4L models with manual transmission produced between 1998 and 2001. This hose forms part of the engine’s coolant return circuit, transferring coolant from the engine return pipe to the main cooling system distribution pipe.

Fits:
Porsche 996 C2 3.4L 1998 - 2001 MANUAL

Diagram ref no 3

This product supersedes Porsche's old part numbers: 99610664156, 99610664158.

The coolant return hose allows coolant to flow back through the engine’s cooling circuit after absorbing heat from the engine. This circulation allows the cooling system to maintain stable engine operating temperatures and prevents overheating.

A properly functioning hose ensures uninterrupted coolant flow and supports efficient temperature control.

Function
•  Coolant Return Flow: Transfers coolant from the engine return pipe to the cooling system distribution pipe
•  Temperature Regulation: Supports the engine thermostat and radiator system
•  Cooling System Integrity: Maintains sealed coolant circulation under pressure
•  Engine Protection: Helps prevent overheating and coolant leaks

Coolant hoses are constantly exposed to heat, pressure and chemical contact from coolant. Over time the rubber can harden, crack or weaken, increasing the risk of coolant leaks. Replacing ageing hoses helps maintain cooling system reliability and protects the engine from overheating or coolant loss.

When to Replace.  Consider replacing the hose when:
•   Coolant leaks are visible around hose connections
•   The hose shows cracks, swelling or deterioration
•   During cooling system overhaul or thermostat service
•   As preventative maintenance on higher-mileage engines


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Related, superseded, cross reference or alternative numbers for comparison.

99610664162

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