THERMO & GSKT AY

Engine Cooling Thermostat + Gasket Assembly for Subaru

Keep your boxer engine in the ideal temperature zone . This OEM-style thermostat assembly controls coolant flow so the engine warms up quickly and stays at stable operating temp for clean combustion, power, and long life.

Why you need it

Correct temperature equals smooth idle, better fuel economy, strong heater output, and reduced wear. The included sealing ring prevents leaks and air intrusion that can cause hot spots and corrosion in the cooling system.

How it works

Inside sits a wax-charge capsule. As coolant heats, the wax expands and pushes a rod to open the valve to the radiator. When coolant cools, the spring closes the valve. The gasket seats the housing to keep system pressure tight and circulation stable .

What happens if it’s broken ⚠️

• Stuck closed: rapid overheating, boiling coolant, warped head, possible head-gasket failure.
• Stuck open: overcooling, rich mixture, poor mileage, weak cabin heat.
• Leaking seal: coolant loss, air locks, erratic temp swings.

Tech notes

Drain and refill with fresh coolant, clean mating faces, install the seal correctly (dry or per OEM spec),torque bolts evenly, and bleed air. Quality unit uses stainless spring and high-temp rubber for long service ✅.

Compatibility

• Legacy
• Impreza
• Exiga