Water is designed to maintain normal operating temperature. Water will only perform this function if all other components are operating correctly. Water should include an additive to prevent corrosion and erosion. If your vehicle is driven in either a very cold or very hot climate it may be necessary to add either an anti freeze or anti boil solution. This will only work effectively if the corrosive inhibitor is changed every 12 months.
THINGS TO LOOK FOR
The colour of the water tells a very good story about the condition of the cooling system. Brown water is the worst, clear water is not good; green water is best and it needs to be changed every 12 months to keep the colour at its best.
IS IT EXPENSIVE TO REPAIR?
If your vehicle is pre 1990 then a good corrosive inhibitor, eg Castrol, may be okay. If it is after 1990 then contact your dealer as the seals and welsh plugs require specific inhibitors to protect these components. These additives may be expensive.
TEMPORARY REPAIR AND LONG TERM REPLACEMENT
If your vehicle has brown water, disconnect the heater hose and remove the radiator cap and secure a garden hose in the heater hose and turn on a moderate pressure. This is the best way to reverse flush the cooling system. Please note: this should only be done when the engine is cold. It may require several applications until the water runs clear. It is a good idea to turn the heater tap as this will also flush the heater core, in case it might be partially blocked.