Parts for your 2021 Haval H6-Radiator cap

2021 Haval H6 radiator cap: what’s fitted and what to service

For the 2021 Haval H6, a traditional radiator-mounted cap isn’t used. Technical sources including GWM/Haval owner’s manual guidance for the cooling system, factory service diagrams for the 3rd‑gen H6 platform, and OEM/aftermarket parts catalogues show the vehicle runs a sealed radiator and a pressurised expansion (coolant reservoir) tank. The pressure cap sits on the reservoir, not on the radiator neck. So if someone’s hunting for a “radiator cap” on a 2021 H6, they’ll find only the reservoir pressure cap under the bonnet.

Why the change? Modern cooling layouts move the pressure point to the expansion tank to improve safety, packaging and degassing. With no filler neck on the radiator, there’s less scald risk at the front of the car, better crash packaging, and more consistent system pressure and air separation. It also makes coolant checks simpler—levels are read from the translucent tank, cold.

• It’s a sealed radiator, the reservoir cap is the pressure control point for the whole system.
• Level checks and top-ups are done only at the expansion tank, when the engine is cold.
• The cap’s job is to hold pressure (typically around 110–140 kPa—confirm on the cap or in the owner’s info) and to allow vacuum return as the engine cools.

Servicing tips for the 2021 H6’s reservoir cap: check the rubber seal for nicks, hardening or swelling, inspect the spring and valve for sticking, and replace the cap if there are signs of coolant pushing past the cap, collapsing hoses after cool-down, slow warm‑up/overheating, or if the cap’s warning label is unreadable. Use a genuine or high‑quality equivalent rated to the same pressure as printed on the original cap. Only open the cap when stone cold, and refill with the correct long‑life coolant specified by GWM/Haval (usually a premixed OAT formulation). If the system has been opened, bleed it per workshop procedure to avoid trapped air.

Popular questions

Where is the radiator cap on a 2021 Haval H6?
It doesn’t have a cap on the radiator itself. The system uses a pressurised expansion tank with a screw cap on the coolant reservoir. That cap controls system pressure and is the only place to open the system for level checks or top‑ups—always when cold.

What cap should be used if the original is leaking?
Match the pressure rating printed on the original reservoir cap and choose a genuine GWM/Haval part or a quality equivalent. The rating is typically around 110–140 kPa, but owners should confirm against the label on the cap or the vehicle’s service information to avoid under‑ or over‑pressurising the system.

Can a faulty cap cause overheating or coolant loss?
Yes. A weak cap can vent too early, pushing coolant into the overflow and out of the tank. A stuck cap can prevent vacuum return, collapsing hoses as the engine cools. Either fault can lead to overheating, coolant odour, or low levels. Replacing a suspect cap is inexpensive insurance for the cooling system.