1981 Volvo DL, GL and GLT
by stones, gravel or minor accidents.
Several factors influence the speed at which corrosion will occur:
1. The length of time various parts of a car stay wet. Parts of the car filled with road dirt and water
remain damp for long periods of time even when other parts are dry.
Particular attention should be paid to the underside of the car and floor sections inside.
The floor sections stay wet because moisture collects and remains under the floor matting.
Drain holes located at the bottom of the doors can get clogged with dirt, trapping water inside the door
and causing the door to rust through at the bottom.
2. Corrosion will be accelerated in areas of higher relative humidity, especially where temperatures often
stay above the freezing point and where the atmosphere is affected by industrial pollution, or where salt
is used for de-icing the roads.
Where parts of the car are covered with road dirt containing road salt, corrosion will be accelerated at a
lower relative humidity than if the surface were clean.
3. Increased temperature will cause an accelerated rate of corrosion of those parts of the car which are
not well ventilated to permit quick drying.
4. Industrial pollution and the presence of salt will also accelerate the deterioration of paint finishes.
The foregoing identifies the need for every car owner to keep the car and particularly the underside, as
clean and dry as possible and to repair any minor damage to paint work and protective coating as soon as
The need is more important in those localities where road salt is used for de-icing, the relative humidity
is higher, air pollution is present and temperatures regularly stay above freezing.
pg. 81 Cold weather
Engine cooling system
Volvo recommended anti-freeze/summer coolant should be used all the year round. The cooling system
should always contain water plus anti-freeze and rust inhibitor, even during the summer. Experience has
also shown that extremely weak anti-freeze solutions (10-25 percent) are ineffective for rust protection.
For this reason, the quantity of anti-freeze/summer coolant should amount to about 50 percent of the
solution, that is 5.0 US qts. = 4.8 liters. This lowers the freezing point to-30° F (-35° C).
Alcohol must not be used as an anti-freeze agent since it evaporates at normal engine temperature.
Engine fuel system
During the winter, large variations in temperature cause condensation to form in the fuel tank and can
impair the running of the engine. This can be eliminated by adding special additives to the fuel. There is
less risk of condensation forming in the fuel tank if it is kept full.
Engine lubricating system
During the winter, multigrade oil 10W-40 should be used in the engine. At very low temperatures, below
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