# Flushing radiator

After years of regular driving, radiators can become clogged, both internally and externally.

If, for any reason, the radiator is removed, the fins should be back washed with high pressure water to clean out road grime and obstructions from the fins.

Take care not to hit the fins on an angle with high pressure water as this will close the fins.

Work from the back of the radiator, washing the debris out the front. If necessary, use a brush to break loose debris.

To clean a radiator internally, add a flush chemical to the coolant and follow the directions supplied by the manufacturer of the chemical.

If a radiator is contaminated with oil, from a blown head gasket, it should be removed and flushed outside the system.

E30 M3 Repair Manual V2.7. Copyright ©1999-2001 Koala Motorsport & Brett Anderson