Parts for your 2013 Honda Elysion-Radiator cap

2013 Honda Elysion radiator cap — purpose, checks, and when to replace

For the 2013 Honda Elysion, a radiator cap absolutely is used and relevant. Honda’s factory parts catalogue for the Elysion RR-series lists a CAP, RADIATOR (1.1) as a service item (commonly referenced as 19045-PAA-A01 across K24A/J35A-equipped Hondas). The Honda service manual’s cooling system section also includes a “Radiator Cap Test” procedure, confirming the vehicle relies on a pressurised cap to control system pressure and coolant recovery. Those technical sources establish that the Elysion is designed to run a 1.1 bar cap, not a capless/degas-only setup.

On this model, the radiator cap does more than just close the filler neck. It holds pressure so the coolant’s boiling point is raised, keeps air out, and manages expansion and contraction by feeding excess coolant to the overflow bottle and drawing it back as the engine cools. That stable pressure helps prevent hotspots, hose collapse, and nuisance overheating — all pretty important on long family hauls or around-town school runs.

Good servicing for a 2013 Honda Elysion should include a quick look at the radiator cap every time coolant is checked. The rubber seals need to be supple, the spring should offer firm resistance, and the underside should be free of crusty deposits. If the vehicle has overheated, if the coolant keeps disappearing with no obvious leaks, or if there’s dried coolant staining around the neck, the cap is a prime suspect. Using an OEM-spec 1.1 bar cap (or quality equivalent) keeps the system working as Honda intended.

• Only remove the cap when the engine is stone cold — pressure can cause scalding.
• Inspect the main seal and the smaller return seal for nicks, flattening, or swelling.
• Clean the filler neck so the seals can seat properly.
• Top up with Honda Type 2 coolant (or equivalent premix) if the level’s low.

Replacement is inexpensive and can be treated as preventative maintenance every few years, or whenever there’s doubt about sealing or pressure retention. Many workshops bench-test the cap’s relief pressure, if it doesn’t hold close to its rated value, it’s time for a new one. A fresh, correct-pressure cap helps protect the Elysion’s alloy components, maintains cabin heater performance, and supports reliable cooling in hot Aussie and Kiwi conditions.

Popular questions about 2013 Honda Elysion radiator caps

What pressure rating cap does the 2013 Elysion use?
The Elysion is specified for a 1.1 bar radiator cap (about 16 psi). That rating appears on OEM caps and in Honda parts listings for the RR-series. Sticking with the factory pressure helps ensure proper coolant recovery and stable temperatures.

Where is the radiator cap located on the Elysion?
It’s typically on the radiator filler neck at the front of the engine bay. Some trims may place the filler neck on a short pipe near the upper radiator hose, but it’s still a pressurised cap. The plastic overflow bottle beside the radiator is not pressurised and has its own simple lid.

Can a tired radiator cap cause overheating?
Yes. If the cap can’t hold pressure, coolant can boil earlier, push out into the bottle, and not return properly, leading to overheating or weak cabin heat. Replacing a weak cap is a quick, low-cost fix that often restores normal operation.