Coolant Draining; Drain Valve; Cleaning Of The Cooling Inside System Circuit - KIRLOSKAR DV Series O & M Manual

6.3 Cooling system
The coolant must be changed at intervals of 3000 hours operation or three years whichever comes first.
6.3.1

Coolant draining

Drain Valve

a) Remove the pressure cap.
b) Open the drain valve at the radiator lower part to drain the coolant as the right figure.
c) Loosen the coolant drain plug. Loosen the coolant drain plug of the cylinder block.
Caution : When removing the pressure filler cap while the engine is still hot, cover the cap with a rag, then
turn it slowly to release the internal steam pressure This will prevent a person from scalding with hot steam
spouted out from the filler port.
6.3.2 Cleaning of the cooling inside system circuit (by authorized specialist personnel)
When the cooling system circuit are fouled with water scales or sludge particles, the cooling efficiency will
be lowered.
Investigations have shown that in many cases the poor condition of the coolant and /or the cooling system
accounts for damage to the water pump mechanical seal, The poor condition of the cooling system is
normally due to use of unsuitable or no anti-freezing agents and corrosion inhibitor or defect, not early
enough replaced covers for filler neck and working valves.
If twice in a short time the water pump of an engine develops leases or the coolant is heavily contaminated
(dull, brown, mechanically contaminated, grey or black sings of a leakage on the water pump casing)
clean the cooling system prior to removing that water pump as follows.
a) Drain coolant.
b) Remove thermostats, so that the whole cooling system is immediately flown through when cleaned.
c) Fill the cooling system with a mixture of potable water and 1.5% by volume of cleaner.
d) Warm up engine under load. After a temperature of 60 C is reached, run engine for a further 15
minutes.
e) Drain cleaning fluid.
f) Repeat steps c) and d).
g) Flush cooling system.
Drain Valve
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