why does my BMW 3 Series F30/F31 (2012-2019) overheat while driving

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the engine is cool before starting work to avoid burns.
• Disconnect the battery to prevent electrical issues.

2. Coolant Level Check and Top-Up

• Open the coolant reservoir cap slowly to relieve pressure.
• If low, top up the coolant with the manufacturer's recommended coolant mixture (50/50 distilled water and BMW-approved coolant).
• Replace the cap securely.

3. Replace Thermostat (if faulty)

• Drain the coolant from the radiator using a drain plug.
• Remove the thermostat housing bolts (typically a 10mm socket).
• Carefully remove the old thermostat and gasket.
• Install the new thermostat and gasket, ensuring proper orientation.
• Reattach the thermostat housing and torque the bolts to manufacturer specifications (usually around 10 Nm).

4. Inspect and Replace Water Pump (if needed)

• Remove any components obstructing access to the water pump (e.g., engine cover).
• Disconnect the hoses connected to the water pump.
• Remove the water pump mounting bolts and take out the old pump.
• Clean the mounting surface thoroughly.
• Install the new water pump and torque bolts to manufacturer specifications (typically around 10-12 Nm).
• Reconnect hoses securely.

5. Check and Replace Radiator Fan (if necessary)

• Inspect the fan for any obstructions or damage.
• Disconnect the electrical connector from the fan.
• Remove the mounting bolts securing the fan to the shroud.
• Replace with a new fan if it is not operational or damaged.
• Reassemble and reconnect the electrical connection.

6. Refill Coolant and Bleed System

• Refill the radiator and reservoir with the OEM coolant mixture.
• Start the engine and allow it to reach operating temperature with the radiator cap off to bleed air from the system.
• Once the thermostat opens, check for any air bubbles and top off the coolant as needed.
• Replace the radiator cap securely.