Parts for your 2006 Honda Elysion-Thermostat housing

2006 Honda Elysion thermostat housing — what it does and when to service it

Based on Honda’s own technical sources — the Honda Elysion (RR1–RR5) service manual cooling system section and the Honda Electronic Parts Catalogue for 2006 (Water Pump/Thermostat diagrams) — the 2006 Honda Elysion definitely uses a thermostat housing. Both factory engines fitted to this model, the 2.4-litre K24A and the 3.0-litre J-series V6, place the thermostat inside a dedicated water inlet/outlet housing that bolts to the engine and connects to the lower radiator hose. Comparable Honda manuals for the same engines in the Odyssey/Accord lines show the same layout, reinforcing that the thermostat housing is a normal, serviceable component on the Elysion.

On this vehicle, the thermostat housing does a few key jobs. It seats and seals the thermostat so coolant warms up quickly, then routes flow to the radiator once operating temperature is reached. It also provides the mating point for the lower radiator hose and, depending on engine variant, may integrate coolant bypass passages and sensor bosses. In short, it’s a small casting that keeps the big aluminium bits happy by helping the engine reach temp smartly and stay there under load, in summer heat or a South Island winter.

When it comes time for servicing, a weeping housing, a perished O-ring, or corrosion around the hose neck are the usual cues to act. Many owners replace the thermostat and housing gasket together during a coolant service, especially if there’s any history of overheating or slow warm-up. Genuine or high-quality aftermarket gaskets and the correct Honda Type 2 coolant are worth the small premium — mixing coolants or reusing flattened seals is a false economy.

A sensible approach for the 2006 Elysion is:

• Inspect at every coolant change (roughly 5 years/100,000 km or per service manual).
• Check for pink/white crust at the seam and hose necks, and for staining under the housing.
• Replace the thermostat, housing seal/O-ring, and hose clamps if there’s any doubt.

Replacement is straightforward: drain the coolant, remove the lower radiator hose, unplug any nearby sensors, unbolt the housing, clean the mating surface carefully, install a fresh seal, and refit. Always torque the bolts to the factory spec and bleed the cooling system with the heater on hot until the fans cycle and the upper hose is hot, topping up the overflow. A quick road test and another check for leaks under the bonnet after cool-down finishes the job nicely.

Popular questions about the 2006 Honda Elysion thermostat housing

Where is the thermostat housing on a 2006 Honda Elysion?
On K24A four-cylinder models it sits low on the engine where the lower radiator hose meets the block, near the water pump area. On the J-series V6 it’s also at the lower radiator hose connection on the front side of the engine. If you trace the lower hose from the radiator, you’ll land right on the housing.

What are common signs the thermostat housing or seal needs attention?
Look for coolant smell after a drive, dried pink/white residue around the housing seam, slow coolant loss, or a drip forming under the front of the vehicle. Overheating, temperature swings, or slow cabin heat can point to thermostat issues, which are often addressed at the same time as the housing seal.

Should the thermostat and housing be replaced as a pair?
They’re separate parts, but it’s common to replace the thermostat and the housing gasket/O-ring together. If the housing neck is pitted or cracked, replace the housing too. Doing them together during a scheduled coolant service saves time and helps prevent repeat leaks.