Parts for your 2013 Ford Falcon-Radiator cap

2013 Ford Falcon radiator-cap: what it does and when to replace it

On the 2013 Ford Falcon (FG MkII), a pressure “radiator cap” is absolutely used—just not on the radiator neck. Technical references including the Ford Australia Workshop Manual (Section 303-03, Cooling System—General Information) describe a sealed, pressurised cooling system that fills and vents via a remote coolant reservoir (often called a degas bottle) fitted with a pressure cap. Australian aftermarket catalogues for the FG/FG MkII from well-known suppliers also list a reservoir-mounted pressure cap in the 135–140 kPa (around 20 psi) range. So while the radiator itself has no cap, the vehicle does rely on a pressure cap on the expansion tank to regulate system pressure.

For the 2013 Falcon owner, that cap is more than a lid—it’s the gatekeeper for temperature control and long-term cooling system health. The cap seals the system to a set pressure, raising the coolant’s boiling point so it can handle Aussie summer heat and long highway pulls without bubbling over. Inside the cap, a pressure valve releases excess pressure to the reservoir if things get too hot, and a vacuum valve lets coolant draw back as the engine cools, preventing hose collapse and keeping the system topped up.

Keeping that cap in good nick is cheap insurance. If the seal’s tired or the spring’s weak, pressure drops, the boiling point falls, and the Falcon can start running hot or burping coolant. It’s smart to inspect the cap at every service: look for brittle or cracked rubber, crusty deposits, damaged threads on the bottle, or hoses that flatten as it cools—classic signs the vacuum valve isn’t doing its job. Many techs recommend replacing the cap at the same time as a coolant change or any major cooling repair, or around the 5-year mark, especially if the vehicle tows or sees hot-climate use.

• Only remove the cap when the engine is completely cold—pressure and hot coolant can cause injury.
• Use the correct pressure rating (typically around 135–140 kPa for FG MkII) and quality OEM-equivalent parts.
• After replacement, run the engine to operating temp and check for leaks, firm upper hose feel, and stable temps.
• If overheating, coolant loss, or repeated hose collapse persists after a new cap, pressure-test the system and inspect the reservoir for cracks.

Bottom line: on a 2013 Ford Falcon, the “radiator-cap” lives on the coolant reservoir and is critical to keeping the Barra’s cooling system stable, efficient, and drama-free.

Popular questions about 2013 Ford Falcon radiator-cap

Does a 2013 Ford Falcon have a radiator cap on the radiator?
Not on the radiator itself. The FG MkII uses a pressurised reservoir (degas bottle) with a pressure cap. That cap performs the same job—controlling system pressure and coolant flow—as a traditional radiator-mounted cap.

What pressure rating cap should be used?
Common listings for the FG/FG MkII specify approximately 135–140 kPa (about 20 psi). Sticking with the factory-specified rating helps maintain the correct boiling point and protects hoses, seals, and the plastic reservoir from undue stress.

How often should the cap be replaced?
Inspect at every service and replace if the seal is perished, there’s crusty residue, the spring feels weak, or hoses collapse after cool-down. As preventative maintenance, many workshops replace the cap with each coolant service or around five years, especially in hotter climates or towing duty.