Nanni QLS 65T, User Manual

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56
S08 MAINTENANCE
HEAT EXCHANGER SERVICE
Have the engine heat exchanger inspected at intervals.
Get on hand spare new seals before servicing this unit.
It is highly recommended to have this service performed
by a seasoned marine service tecnician.
HEAT EXCHANGER INSPECTION:
1. Close sea cocks and drain the sea water system.
2.Open drain cock on cylinder block and drain
approximately two gallons of engine coolant into a clean
container. Close drain cock.
3. Loosen clamp (A) and remove duct from rear end cap
(B).
4. Remove the two end mounting cap screws and
remove end cap (B) with heat exchanger core (C) from
rear of engine.
It is recommended that both end caps be removed
when cleaning the heat exchanger core.
Use a brass rod to clean out any buildup in each heat
exchanger tube. Run the rod the entire length of each
tube to push debris out. Flush the heat exchanger tubes
with clean water, making sure all tubes are cleared of
debris.
If you suspect that your heat exchanger core is
defective, have your authorized Nanni representative to
handle this task. Replace the heat exchanger core as
required. Remove and thoroughly clean with water the
manifold/heat exchanger housing if needed.
Inspect end cap O-rings (D). O-rings may be reused if
not worn nor flattened. Lubricate front and rear end cap
O-rings with clean multi-purpose grease. Thighten cap
screws to 24 Nm (18 lb-ft).
Fill up heat exchanger with coolant mix. Check for
leaks.Start the engine for a few minutes. Check again
for leaks.