An important consideration when purchasing any used diesel
car is its servicing requirements and reliability. Diesel
engines offer many advantages over used cars fitted with
petrol engines. Two of the major contributing factors to
improved reliability are the physical properties of diesel
fuel, and secondly the design and construction of a diesel
engine.
Diesel Fuel Lubrication
Diesel fuel is actually quite different to petrol. It provides
much greater lubrication to the engine than petrol and actually
offers a significant level of protection to the internal
components. Piston rings and cylinders particularly benefit
from improved lubrication and rarely do diesel engines suffer
from wear of these components.
Secondly diesel engines are designed and engineered to
withstand higher operating stresses encountered with their
higher compression ratios. This is important because virtually
all components within a diesel engine are manufactured using
stronger materials which resist premature failure and provide
an extended working life. Diesel engines have fewer complicated
electrical systems, and so the potential for them to fail
is removed entirely. They also run at a lower rpm than petrol
engines, so are not subjected to such a harsh high revving
life.
Regular Oil Changes
Improved reliability is reliant on following manufacturers
suggested service intervals. Turbochargers are dependant
on a supply of clean engine oil to ensure they run smoothly
and remain sufficiently lubricated, they are often a component
which is susceptible to premature failure if the engine
is not serviced according to recommended guidelines.