Civic Type R K20C

Ensure the o-ring is installed evenly and is not damaged.

Drain engine coolant enough so the remaining level is lower than the upper radiator hose.

Disconnect the upper rad hose from the engine thermostat housing.

Remove the three 10mm M6 bolts that hold the housing in place.

Install the Hybrid Racing thermostat and torque bolts to 9ftlb.