Parts for your 2014 Honda Stream-Thermostat

2014 Honda Stream Thermostat — What It Does and When to Replace It

Based on Honda’s technical literature for the Stream (RN6–RN9) and the Honda Electronic Parts Catalogue, the 2014 Honda Stream uses a conventional, wax‑pellet engine coolant thermostat. It’s housed in a bolt‑on alloy housing on the engine, controlling coolant flow to the radiator on both the 1.8L R18A and 2.0L R20A i‑VTEC engines. Honda workshop manuals list inspection specs and removal/installation steps for the thermostat, confirming it’s a standard, serviceable part on this model.

In day‑to‑day driving, the thermostat’s job is simple but critical. It keeps the Stream’s engine at the sweet‑spot temperature, closing when cold so it warms up quickly, then opening as it reaches operating temp so heat is shed through the radiator. That means better fuel economy, smoother running, proper cabin heat, and stable emissions. If it sticks shut, the engine can overheat. If it sticks open, the engine runs too cool, the heater’s weak, and fuel economy drops because warm‑up takes ages.

Thermostats aren’t a scheduled replacement item with Honda, they’re typically replaced on condition. That said, on an older Stream or one that’s clocked plenty of kilometres, swapping the thermostat proactively when doing a major cooling system service (fresh Honda Type 2 coolant, hoses inspected) isn’t a bad shout. Always fit a quality unit and a new O‑ring/gasket, clean the housing faces, and tighten bolts to workshop‑manual spec. After refitting, bleed the cooling system properly: heater on hot, use a spill‑free funnel, idle until the radiator fan cycles a couple of times, and top up the overflow bottle to the mark.

• Watch for tell‑tales: slow warm‑up, fluctuating temp gauge, poor heater output, pink/blue coolant crust near the housing, or an overheating warning.
• A scan tool can confirm coolant temps and help spot a lazy thermostat without guesswork.
• If the bonnet’s been up for coolant work, check for leaks after the first few drives and recheck the level when cold.

Get the thermostat sorted and the Stream will run bang on temp, even on a scorching arvo or a frosty morning, with no dramas.

FAQs

Where is the thermostat on a 2014 Honda Stream?
It’s mounted in an alloy housing on the engine, near the radiator hose connection. On both R18A and R20A engines, access is from the front of the engine bay. Remove the intake ducting for room, drain enough coolant, then unbolt the housing to reach the thermostat and O‑ring.

What are the signs the thermostat needs replacing?
Common signs include the temp gauge sitting low on the open road, slow or no cabin heat, fluctuating temps, or overheating under load. A check‑engine light with a coolant temperature code can also point to a thermostat that’s stuck open or shut. Confirm with a scan of live coolant temp before replacing.

Do I need genuine Honda coolant when changing the thermostat?
Honda recommends Honda Type 2 (blue, premixed). It’s silicate‑free and designed for the alloy components in the cooling system. Using the right coolant helps protect the pump, radiator, and the thermostat itself, and it extends service life. Top up only when the engine’s cold and bleed out any air.