Preventive Maintenance Checks and Services for Electrical Power Systems (Continued)
CHECK FOR AND HAVE
IS NOT READY/
REPAIRED OR ADJUSTED
B D A D
3) The heat exchanger and coolers
should be serviced every season.
Depending on operating conditions,
this period may have to be reduced.
Normal operating temperatures will
vary slightly from engine to engine
because of design tolerances, installa-
tion, and hull variations. Once the nor-
mal operating temperature has been
establihsed for a particular engine,
any excessive rise in temperature
should be considered abnormal and
immediately investigated. If a cooling
system problem is suspected (or com-
firmed) the following guidelines will
provide a means for isolating the
The coolant in an operating or recently
stopped engine is very hot and under pres-
sure. If the filter pressure cap is suddenly
removed the liquid may spurt and cause
injury by scalding. Always stop an engine
and allow it to cool before removing the cap.
Once cool, loosen the cap slowly to relieve
(a) Check the coolant level in the
header tank and ensure the proper
pressure cap is being used.
(b) Check the sea cock and strainer
for obstructions; clean where nec-
(c) Check the seawater pump
impeller. Replace if damaged.
Ensure that no pieces of the
impeller (if broken) have passed
into the connecting pipes (i.e., inlet
and outlet) to restrict water flow.
(d) Check heat exchanger for
obstructions within the cooling
core tubes on the seawater side.
Once the end cap and/or plates
are removed, any scaling within
the core tubes can be removed by
passing a rod (slightly smaller than
the internal bore) thru the tubes.
Do not use excessive force when
pushing the rod thru the tubes.