All hoses and connections in the cooling and heating system should be checked carefully for leaks.
Check particularly the joints at the water pump, water control valve, cylinder head gasket, cylinder block core plugs, drain plugs, radiator and all hoses and connections.
Examine the hoses for perishing, swelling, or other damage. Inspect the radiator fins to ensure they are not damaged, or clogged with dirt.
Fan Belt Check the tension and condition of the fan belt as detailed later under the appropriate heading.
Coolant Level The coolant level in the radiator should be checked at least weekly, and topped up as necessary. Check the level when the engine is cool. If the system is at normal operating temperature, allow it to cool first. Muffle the cap with a thick cloth to protect the hands against scalding and turn the cap slowly anti-clockwise to the first stop to release the pressure in the system through the over-flow tube before completely removing the cap.
The coolant level should be up to the 'level indicator' plate inside the radiator filler neck, or to the bottom of the filler neck where no plate is fitted. If the level in the system has fallen appreciably, suspect a leak in the system; check the hoses and hose connections first.
NOTE: When the system contains anti-freeze, ensure that the strength of the mixture is maintained when topping up.
Anti-freeze Because of the properties of anti-freeze in raising the boiling point of the coolant, as well as lowering the freezing point, it is recommended that an 'All-Season' type anti-freeze be used permanently in the cooling system to afford maximum protection against both freezing and over-heating. The presence of a corrosion inhibitor in most anti-freezes will also help to prevent corrosion and the formation of scale in the system.
During the winter months an anti-freeze mixture MUST be used in the system to protect against frost damage. The concentration of the solution will depend on the degree of protection required, and dilution should be carried out in accordance with the manufacturer's instructions. As a guideline a 25% solution of anti-freeze by volume will remain fluid down to - 13 'C (9 'F), and a 45% solution will give protection down to approximately -32'C (- 26'F).
Before filling the system with anti-freeze solution, inspect all hoses, hose connections and cooling system joints. Tighten or renew where necessary. After adding the antifreeze, run the engine up to normal operating temperature and check for leaks. A label should be attached to the radiator to record the date of filling.
The anti-freeze concentration in the system should be checked periodically and in any case before the beginning of the winter season. The specific gravity of the mixture can be checked using a suitable hydrometer. The specific gravity of a 45% concentration solution should be 1.065 providing no other additive is in the cooling system.
Flushing The cooling system should be completely drained, flushed and refilled with a fresh mixture of anti-freeze and water at least every two years or as recommended by the anti-freeze manufacturer.