ENGINE COOLANT
The engine coolant ensures that the engine operates at safe temperature levels.
The 50-50 mix of coolant and water creates a fluid that protects against freezing
in cold weather, lubricates the water pump, keeps rust and oxidation at bay, and
absorbs heat from the engine. This heat is carried to the radiator where it is
released. If coolant is left in the engine too long, it no longer performs these vital
functions. What should you look for when checking your vehicle’s engine
coolant? Color, consistency, and smell.
Color
The color of healthy engine coolant is green (for ethylene glycol) or orange (for
Dexcool). A rusty color indicates that the rust inhibitor in the coolant has broken
down and it can no longer control rust and scale buildup. The system must be
cleaned and flushed and a fresh 50-50 mix of coolant installed to restore
integrity. A milky color indicates the presence of oil in the system. This is not
good; it usually means that a head gasket, intake manifold, or transmission oil
cooler is leaking oil or transmission fluid into the engine coolant. This is a
deadly mix that will kill an engine or transmission in short order. Get it taken
care of immediately.