Sea Water Pump, Heat Exchanger - Beta Marine Beta 10 Operator's Maintenance Manual

SEA WATER PUMP AND COOLING SYSTEM -
CAUTION
Before working on the sea water
system ensure that the sea cock is
in the off position.
(1) It is very important that the
correct sea water flow is
maintained to cool the closed
circuit system of the engine. The
key component in this system is
the sea water pump impeller.
This should be checked every
year by removing the circular
plate (see fig. 2h)
CLEANING THE HEAT EXCHANGER TUBE STACK AND REPLACING WASTING ZINC ANODE
(1) The wasting zinc anode should
be checked every six months and
replaced every year or as
necessary. The anode is attached
to the bolt inserted in the aft end
cap of the heat exchanger. See
fig. 2j.
(2) Unscrew the bolt and replace the
complete unit with a new one.
(3) Check for leaks.
(4) It is possible for fine sea weed
and other debris to get past the
inlet filter and into the tube stack.
This should be removed and
cleaned. See fig. 2k.
(5) Drain off coolant into a bucket.
(Heat exchanger-cooled engines)
(2) Withdraw the rubber impeller
from its drive shaft as shown.
See diagram 2i.
(3) Check impeller for cracks in the
rubber, excessive wear or lost
vanes. Replace with a new
impeller as necessary.
Note
: If any pieces of rubber
impeller are missing then they must
be found as they are most likely to be
trapped in the entrance to the heat
exchanger cooling stack. See
'Cleaning Tube Stack'.
(6) Unscrew the 2 end cap retaining
bolts (one each end of the tube
stack). Remove the 'O' rings and
pull out tube stack. Clean tube
stack and end caps.
(7) Re-assemble using new 'O' rings.
Do not overtighten end cap bolts
and make sure the tube stack is
the right way round.
(8) Re-fill engine with water/anti-
freeze solution and run engine up
to temperature to check for leaks.
12
Fig. 2h
Fig. 2i
Fig. 2j
Zinc
Anode
Fig. 2k