Engine Coolant Expansion Reservoir Overflow Tank for BMW and Mini Cooper 118i I3 I3s I8 318i

Engine Coolant Expansion Reservoir Overflow Tank is an essential aftermarket replacement designed to fit BMW models including 118i, I3, I3s, I8 and 318i, as well as the 2014–2019 Mini Cooper. This expansion reservoir helps manage coolant expansion and overflow, maintaining proper pressure and preventing air pockets that can lead to overheating or coolant loss. Engineered to mirror the OEM fit, it supports reliable cooling system performance and reduces the risk of radiator and hose strain caused by fluctuating coolant levels.

Crafted to meet the needs of drivers who require a dependable, cost-effective replacement, this tank is a practical solution when your original reservoir shows signs of cracking, leaking, or deformation. It’s an ideal choice for maintenance enthusiasts performing routine cooling system service or for those restoring the vehicle to peak operating condition. Note: Compatibility is for reference only. Before purchase, please compare the Part Number with your original part. It must be the same to ensure a correct replacement.

Benefits & Tips

• Restore proper coolant circulation and pressure management to prevent overheating and improve engine longevity.
• Ideal when servicing the cooling system or when your original reservoir shows cracks, leaks, or deformation.
• After installation, bleed the cooling system as required to ensure no air pockets remain and the system stabilizes quickly.

Product specifications

• Brand: POKESS
• Product: Engine Coolant Expansion Reservoir Overflow Tank
• OE Numbers: 17137823626, 17137539267
• Compatible with: BMW 118i I3 I3s I8 318i (2014–2019); Mini Cooper (2014–2019)
• Reference codes: FRT1908C, FRT2001C
• Origin: Mainland China
• Notes: Compatibility is reference only. Please compare the part number with your original part to ensure a correct replacement.

Package includes:

• 1 x Engine Coolant Expansion Reservoir Overflow Tank

Warnings / reminders

• Compatibility is reference only—verify the Part Number matches your original part before purchase.
• When replacing, ensure the engine is cool and perform the appropriate cooling system bleed procedure after installation.

All electronic and mechanical equipment, devices and machines sold by InterCyprus to EU countries are CE certified and carry a two year warranty.

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