Parts for your 2017 Mitsubishi Eclipse cross-Radiator cap

2017 Mitsubishi Eclipse Cross radiator cap — is there one?

Short answer: a traditional radiator cap on the radiator itself isn’t used on the 2017 Mitsubishi Eclipse Cross. Mitsubishi’s cooling layout for this model uses a sealed radiator and a pressurised coolant expansion (degas) tank with a pressure cap on the tank, not the radiator.

This design is confirmed in Mitsubishi technical literature — the Eclipse Cross service manual cooling system section describes filling and pressure-checking via the expansion tank, and the Mitsubishi electronic parts catalogue lists a pressure cap for the reservoir, while the radiator assembly appears as a sealed unit without a cap neck. Owner’s manual guidance also points drivers to the coolant tank for level checks and top-ups, again indicating no radiator-mounted cap.

Why the change from a radiator cap to a reservoir pressure cap? Modern engines and tighter packaging. A remote, pressurised tank mounted high in the bay becomes the highest point in the system, which makes air bleeding easier and reduces hot spots. It also improves safety — fewer people are tempted to open something on a scorching radiator — and helps keep the radiator more compact and durable by deleting the cap neck.

• Safety: Opening a hot cap can cause scalding, the remote tank keeps hands away from the radiator core.
• Serviceability: The tank is the single fill point, simplifying top-ups and pressure testing.
• Reliability: A sealed radiator reduces potential leak points and helps maintain stable system pressure.

So, if someone is shopping for a “radiator-cap” for a 2017 Mitsubishi Eclipse Cross, what they actually need is the coolant reservoir pressure cap that regulates system pressure and allows coolant to move between the tank and the system as it heats and cools. Always check that the replacement cap matches the vehicle’s specified pressure rating and sealing style, and only remove it when the engine is completely cold.

FAQs

Does the 2017 Mitsubishi Eclipse Cross have a radiator cap?
It doesn’t have a cap on the radiator itself. The pressure cap lives on the pressurised coolant expansion tank. Checks, filling and pressure testing are all done at that tank.

Where should coolant be topped up on a 2017 Eclipse Cross?
Top up only at the coolant expansion tank when the engine is completely cold. Use the coolant type specified in the owner’s manual and fill to the “FULL/COLD” mark. If the level keeps dropping, have the system checked for leaks.

What if the vehicle overheats — can the cap be opened?
Don’t open the cap when hot. Let it cool fully, then check the level at the tank. Persistent overheating warrants a workshop inspection, including a pressure test and a check of the reservoir cap’s seal and relief function.