Boigevis engine coolant thermostat housing assembly

Description

Boigevis engine coolant thermostat housing assembly is designed for Mercedes-Benz M270 engine. The M270 is a 4-cylinder turbocharged engine commonly found in models like the W176 A-Class, C117 CLA-Class, and X156 GLA-Class. Common reference numbers for this unit include 2702000615, 2702000415, and the updated 2702002200.
Included Components: The kit typically contains the plastic thermostat housing, the integrated thermostat unit, a sealing O-ring, and mounting bolts.

Replacement Overview (For Repair Shops)

Replacing the thermostat on an M270 engine is often done to address coolant leaks from the plastic housing or fault codes like P012800 (coolant temperature below thermostat regulating temperature).

1. The thermostat is located under the inlet manifold. For full access, you may need to remove the airbox, intercooler pipe, and throttle body.
2. Drain the coolant partially (roughly 2 gallons) to ensure the level is below the housing before removal.
3. Disconnect electrical plugs and five coolant hoses. Use an E10 Torx socket to remove the mounting bolts.
4. Clean the engine block sealing surface. Install the new unit, ensuring the O-ring is properly seated, and tighten bolts evenly.
5. Refill with approved Mercedes-Benz coolant and run the engine to bleed air from the system.

Common Failure Symptoms

Overheating: If the thermostat is stuck closed, preventing coolant flow to the radiator.
Slow Warm-up: If stuck open, the engine takes a long time to reach operating temperature, leading to poor fuel economy and weak cabin heat.
Visible Leaks: The plastic housing is known to crack over time, leading to external coolant loss