Febi discusses some common problem areas and which vehicles are affected.
Engine oil cooler
Function
To assist the cooling of the engine oil.
Failure
O-ring seals – can harden and crack over time and leak engine oil or coolant. Internal failure, possibly caused by corrosion due to incorrect coolant servicing or incorrect coolant type being used.
Oil mixed with the coolant – if the oil cooler fails internally, traces of oil will be found in the coolant, oil is forced into the cooling system due to being a higher pressure than the cooling system, when the engine is running.
Coolant mixed in the engine oil – once the engine is switched off, the cooling system is still under pressure, coolant can be forced into the engine oil.
To fit
Dacia, Nissan and Renault 1.5dCi engine various models.
Coolant expansion tank
Function
The coolant expansion tank is one part of a vehicles cooling system, which is designed to keep the engine operating at exactly the correct temperature. The sealed cooling system is partially filled with air; the air in the expansion tank provides a ‘cushioning’ effect which allows the heated coolant to expand without causing the cooling system to fail. As the coolant heats up and expands the tank prevents the system from becoming over pressurised.
Cause of failure
The coolant tank fitted to the models listed above is a very common failing item. With age the plastic becomes brittle, yellow in colour and is prone to cracking due to continuous exposure to the engine coolant heat cycles. This results in the coolant leaking, which appears in the luggage compartment area.
The inlet and outlet pipes on the tank that the tubes attach to feed to an integrated manifold on the engine bulkhead. These are also vulnerable and can break leading to coolant leaks. It is advised that the coolant tank be replaced if the original part has become yellow with age to prevent unnecessary future coolant leak issues.
If the transmission requires removal for another repair, it is recommended the coolant tank is checked and replaced at this point, as the access to the tubes inside the engine compartment make installation less complicated with the transmission removed.
The febi replacement is manufactured from high quality Polypropylene materials.
