Frost Precautions - Triumph Spitfire MK3 Handbook

Frost Precautions

The car heater cannot be completely drained by normal
methods. Therefore frost damage will not be prevented by merely
draining the radiator.
For your protection during freezing weather, an approved
anti-freeze solution should be added to the coolant in the
radiator. Because of the searching effect of these solutions,
ANTI-FREEZE CONCENTRATION
Complete Protection :-
Vehicle may be driven away immediately from cold
Safe Limit:-
Coolant in mushy state. Engine may be started and vehicle driven
away after short warm-up period
Lower Protection Limit:-
Prevents frost damage to cylinder head, block and radiator
Engine should NOT be started until thawed out
advise your Dealer to check the system for leaks before adding
the anti-freeze
At certain temperatures glycol water solutions adopt a
"mushy" state with a viscosity which impairs circulation and can
immobilise or damage the water pump. Therefore, consult the
following chart before adding anti-freeze, for the degree of frost
protection required.
25%
10°F (-12°C)
0°F (-17°C)
-14°F (-26°C) -22°F (-30°C)
COOLING SYSTEM
30% 35%
3°F (-16°C) -4°F (-20°C)
-8°F (-22°C) -18°F (-28°C)
-28°F (-33°C)
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