MX-5 NC Coolant Expansion Tank

The coolant expansion tank in third-generation Mazda MX-5 (NC) models is made of three plastic parts welded together using friction welding. Over hundreds of heating and cooling cycles, as well as exposure to atmospheric conditions, these plastic joints tend to crack—especially at the connection between the filler neck and the main tank. A failure in this weld results in a sudden pressure drop in the cooling system, coolant loss, and ultimately, engine overheating

The MAD fabworx coolant expansion tank is made of 3.0 mm thick aluminum sheet, TIG-welded for superior durability against thermal cycles. Additionally, the tank features internal baffles to minimize coolant movement during sudden maneuvers and enhance structural rigidity. It also includes a liquid level indicator made of aluminum and natural glass, resistant to temperatures above 150°C.

Every MAD fabworx tank is pressure tested up to 4 Bar (over 350% of the system's operating pressure) to ensure reliability. The tanks are powder-coated for a durable, high-quality finish.

Key Features:

• Material: 3.0 mm thick aluminum sheet
• Welding method: TIG welding
• Internal baffles for added strength and reduced fluid movement
• Liquid level indicator resistant to temperatures up to 150°C
• Finish: Powder-coated (fine black texture – matte)
• Pressure tested: Up to 4 Bar (system pressure up to 1.3 Bar)

Application:
Mazda MX-5 (Miata) NC (2006-2015) – all engine versions