Engine coolant expansion tank kit. Porsche 986 Boxster / 987.1 Boxster 1997-06  ❭  COOLTANKKIT986.1

Engine coolant expansion tank kit.
The kit combines a coolant expansion tank, a pressure cap, and long-life antifreeze concentrate to deliver a complete coolant system refresh.

Fits:
Porsche 986 Boxster 1997 - 2004
Porsche 987.1 Boxster 2.7L / 3.2L 2005 - 2006 (9625, 9626)

Diagram ref no 8, 11, 26, 27

This OE Match kit is engineered for Porsche vehicles that utilise 99610614708 style expansion tanks - most commonly fitting Porsche Boxster 986 (1997-2004) and 987 (2005-2006) models. Always verify fitment with your specific year, engine and chassis before ordering.

The engine coolant expansion tank kit includes:
• 99610614708/1 × 1 – OE Match Coolant Expansion Tank: Precisely manufactured replacement reservoir designed to match the original Porsche part used on Boxster models. It collects excess coolant as it expands under heat and releases it back into the system as it cools down.

•  99610644704/1 × 1 – OE Match Expansion Tank Cap: A direct-fit cap that seals the coolant reservoir and helps maintain proper pressure in the cooling system, aiding heat control and preventing coolant loss.

•  00004330194 × 5 – Comma Antifreeze Coolant (1 L Red, 5-Year Concentrate): Premium antifreeze concentrated coolant that, when mixed correctly with water, delivers long-lasting protection against freezing, boiling, and corrosion.

This kit brings together all the primary components you need when servicing or refreshing the coolant expansion side of your engine’s cooling system.

The expansion tank accepts expanding coolant from the radiator and engine as temperatures rise, storing it safely and helping maintain correct coolant levels. The cap seals the system and maintains the right amount of pressure, allowing the cooling system to function efficiently. The antifreeze provided offers long-term protection against corrosion, freezing and overheating - crucial to preserving engine health and reducing wear.

Over time, the original plastic tank can become brittle or crack due to heat cycling and age, which may lead to leaks, coolant loss, or air infiltration that disrupts coolant circulation. A failing pressure cap can no longer maintain correct system pressure, reducing cooling efficiency. Replacing these components with OE Match parts helps restore reliable coolant containment and pressure stability - helping prevent costly overheating and engine damage.

Replace these parts when you notice any of the following conditions:
•  Cracks or visible leaks around the expansion tank
•  Discolouration or brittleness of plastic components
•  Coolant level fluctuations without visible leaks
•  Overheating symptoms or reduced cooling performance
•  Routine coolant system maintenance interval is due

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