Heater hose. Porsche 987.2 Boxster / Cayman 2009-12  ›  98710621230

Heater Hose – Porsche 987.2 Boxster / Cayman 2009–2012 – 98710621230

This replacement heater hose is designed for the cooling and cabin heating system. It carries engine coolant through the heater circuit, helping maintain reliable cabin heating and correct coolant circulation.

Fits

• Porsche 987.2 Boxster 2.9L 2009–12.
• Porsche 987.2 Boxster S 3.4L 2009–12.
• Porsche 987C.2 Cayman 2.9L 2009–12.
• Porsche 987C.2 Cayman S / Cayman R 3.4L 2009–12.

Diagram Ref No 19

What This Product Does

This hose provides a coolant connection within the heating circuit. Its role is to convey coolant through the connected system, allowing circulation associated with cabin heating. Although shown alongside the expansion tank and associated fittings, the supplied component is a hose, not a coolant reservoir.

Functions

• Conveys coolant within the heater circuit.
• Provides a connection between adjoining components.
• Contains coolant along the hose connection when correctly installed.

Technical Details

• Genuine Porsche component, part number 98710621230.
• Diagram description: Heating hose.
• Listed diagram quantity: 1.
• Diagram application codes: A120, A121.
• Applications include the supplied 987 MKII Boxster and 987C MKII Cayman variants.
• Shown in the coolant-system assemblies for 987.2 Boxster / Boxster S and 987C.2 Cayman 2.9L / 3.4L, 2009–12.

Symptoms of Fault

• Damp patches or dried deposits at hose joints.
• A coolant odour following use.
• Coolant level dropping repeatedly or a low-level warning.
• Splits, swelling or hardened sections visible during inspection.
• Abnormally high coolant temperature or escaping steam.
• Weak cabin heating associated with insufficient coolant or trapped air.

These signs can have other cooling-system causes; inspect the hose and neighbouring connections before deciding which component needs replacement.

Why Replacement Matters

Repeated heating, internal pressure and movement can gradually degrade a coolant hose. Renewing a confirmed leaking or damaged component addresses the defective connection rather than relying on repeated coolant top-ups. Examine adjoining fittings, clamps and other hoses for deterioration while carrying out the repair. Follow the applicable Porsche workshop instructions for filling and bleeding after installation.

FAQs

Can leakage appear only after driving?
A small defect may become apparent as coolant temperature and system pressure increase, even if the connection appears dry during a cold inspection.

Do nearby connections need checking?
Inspect the mating fittings and clamps as well as the hose. Deposits around a joint do not establish which individual component is responsible.

How can slight coolant seepage be traced?
Pressure testing can help locate a leak that is difficult to identify visually.