1981 Volvo DL, GL and GLT
The risk of overheating is greatest, especially in hot weather, when:
- towing a trailer up steep inclines for prolonged periods at full throttle.
- idling for prolonged periods while the air conditioning system is in operation.
- stopping the engine suddenly after high speed driving, so-called after-boiling.
To avoid overheating, the following rules should be followed.
Reduce speed and downshift when towing a trailer up long steep inclines. The risk of overheating can
be reduced by switching off the air conditioning system for a short while.
Do not let the engine idle unnecessarily.
Do not stop the engine immediately after high-speed driving, but allow the engine to idle for 1/2 - 1
minute before switching off.
When the risk of overheating is imminent, or in the event of overheating, (the temperature gauge goes
repeatedly into, or stays continually in, the red section) the following precautions should be taken:
Switch off the air conditioning system.
Stop the car and put the gear lever into neutral position-position N. Do not stop the engine!
Increase the engine speed to approx. 2000 r/min (twice idling speed).
Check the level of coolant in the expansion tank. Top-up, if necessary.
Check coolant level
The cooling system must be filled with coolant and not leak to operate at maximum efficiency. Check
the coolant level when filling fuel. The level should be between the "MAX" and "MIN" marks on the
expansion tank. The check should be made with particular thoroughness when the engine is new or the
cooling system has been drained.
Do not remove the filler cap other than for topping-up with coolant. Frequent removal may prevent
coolant circulation between the engine and the expansion tank during engine warming up and cooling.
Top up with coolant
Top up with coolant by filling the expansion tank when level is at the "MIN" mark. Use a mixture of 50
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