Coolant Drain; Freshwater System Flushing; Coolant Filter. Change - Volvo Penta D12-AUX Operator's Manual

Maintenance: Freshwater system
48

Coolant drain

1. Remove the filler cap from the expansion tank
and open the vent tap by the turbocharger.
2. Connect a suitable hose to each drain point, refer
to section "Drain points". Open the drains and al-
low the coolant to drain off into a suitable vessel.
IMPORTANT! Check that all coolant really does
drain out. Deposits may need to be cleared
away, inside the drain plug(s)/tap(s).
3. Continue with all the drain points until all have
been opened and all coolant has been drained
off.
4. Drain all other systems connected to the freshwa-
ter system, e.g. heater, water heater, etc.
5. Close all drains.

Freshwater system flushing

The system should be flushed before changing coo-
lant to avoid inferior cooling performance due to de-
posits in the cooling system.
1. Drain the coolant as described earlier.
2. Insert a hose into the filler opening on the expan-
sion tank and flush with fresh water.
3. Flush until the water running out of the drainage
points is clean.
4. Close all drain points when the flushing water has
run out.
5. Fill with coolant. See section coolant filling when
empty.

Coolant filter. Change

IMPORTANT! Do not change the filter when the
coolant is changed. The concentration of rust-preven-
ter in the coolant can become too high, which would
cause foaming and impaired cooling.
1. Clean the filter bracket.
2. Close the filter tap (1), (position A).
3. Unscrew the filter with a suitable wrench.
4. Clean the filter mating surface on the filter brack-
et.
5. Moisten the seals on the new filter with engine oil
and screw the filter on by hand until the rubber
seal just touches the mating surface on the filter
bracket Then tighten a further 1/2 turn.
6. Open the filter tap (1), (position B).
7. Start the engine and check carefully that no lea-
kage occurs.