Premium Coolant Expansion Tank for Toyota Bus Cooling

Why you need it

This reservoir keeps your engine at the right temperature by managing extra coolant and system pressure. On long runs and steep climbs, it prevents boil-over, keeps the radiator topped up, and protects the water pump, hoses, and head gasket. A healthy overflow bottle is vital for reliable cooling and stable performance.

How it works

When coolant heats up, it expands and flows from the radiator through the overflow hose into the tank. As the engine cools, vacuum draws fluid back, keeping the radiator full. The translucent body shows MIN/MAX levels, while molded ports and a tight cap maintain pressure balance in the cooling loop.

What if it’s broken

Cracks, warped fittings, or a weak cap let air in and coolant out. Expect rising temps, low coolant warnings, steam, sweet smell, poor heater output, and risk of warped head or burst hoses. Puddles under the bay or stained plastic are red flags.

Tech notes

OEM-grade polymer resists heat, UV, and glycol. Install on factory brackets, fit new clamps, and bleed air. Use the correct Toyota coolant mix and inspect the cap seal and overflow hose.

Compatibility

• Coaster