Parts for your 2014 Honda Stream-Radiator cap

2014 Honda Stream radiator-cap: purpose, care and when to replace

Yes, the 2014 Honda Stream uses a pressurised radiator cap. Honda’s RN6–RN9 Stream service manual (Cooling System section: Radiator Cap Test) specifies checking the cap’s holding pressure around 108–137 kPa (approx. 1.1–1.4 bar), and the Honda parts catalogue illustrations show a cap fitted to the engine-side filler neck rather than the translucent overflow bottle. That means the cap is a working pressure valve, not just a simple lid.

On the Stream, the radiator cap does three big jobs: it seals the cooling system so it can run under pressure (which raises the coolant’s boiling point), it relieves excess pressure to protect hoses and the radiator, and its vacuum valve draws coolant back from the overflow bottle as the engine cools. When the cap’s spring gets tired or the seal hardens, the cooling system can’t hold pressure properly, which can lead to slow coolant loss, overheating on hot days, or a top hose that collapses as it cools.

Under the bonnet, the cap lives on the metal/plastic filler neck connected to the upper radiator hose. The translucent reservoir beside it is non‑pressurised, don’t confuse its cap with the real pressure cap. For servicing a 2014 Honda Stream, it’s smart to:

• Inspect the cap at each service for a cracked seal, corroded seat, sticky or wobbly spring, and distorted tabs.
• Pressure-test the cap with a cooling-system tester every 24 months or if there are overheating or coolant-loss symptoms. Match the test to the cap’s rating (about 1.1 bar).
• Replace the cap proactively every 5 years/100,000 kilometres, or immediately if it fails a pressure test.
• Use the correct pressure rating specified by Honda, mixing ratings can cause boil-over or stress the system.
• Wipe the filler neck clean before refitting and ensure the cap is fully seated and locked.

Safety tip: never crack the cap when the engine’s hot. Let it cool completely, use a thick rag, and open it slowly to bleed off any residual pressure. After any cap replacement, top up with the correct Honda coolant (Type 2 premix is typical) and bleed air per Honda’s procedure to avoid hot spots and heater gurgles.

Popular questions about the 2014 Honda Stream radiator-cap

What pressure rating should the 2014 Honda Stream radiator cap be?
Most 2014 Streams use a cap around 1.1 bar (about 108 kPa). Honda’s service data for the RN6–RN9 platform lists a test range of roughly 108–137 kPa. Always match the cap to the under‑bonnet label or service manual for the exact spec fitted to that vehicle.

Where is the radiator cap on a 2014 Honda Stream?
It’s on the engine-side filler neck connected to the upper radiator hose, not on the translucent overflow bottle. The bottle’s lid is not pressurised, the proper pressure cap is the one on the filler neck.

How often should the radiator cap be replaced?
Check it at every service, pressure-test it every two years, and replace it about every 5 years/100,000 kilometres, or sooner if there are signs of leaks, overheating, or if it fails a pressure test.