Kohler 8E - Anticorrosion Zinc; Pressure Cap

TP-6277 10/0320 Scheduled Maintenance
3.5.3 Anticorrosion Zinc
An anticorrosion zinc anode in the heat exchanger
prevents electrolytic corrosion by seawater. When
metals such as iron and copper are exposed to a highly
conductive liquid (seawater), the iron gradually rusts.
The anticorrosion zinc anode has chemical properties
which cause the seawater to react to it rather than to the
engine components.
Check or replace the anticorrosion zinc anode as listed
in the service schedule. See Figure 3-9 and use the
following procedure.
12
1. Anticorrosion zinc anode (plug)
2. Heat exchanger
ADV5661-
Figure 3-9 Anticorrosion Zinc Plug Location
1. With the generator set cooled, drain the cooling
seawater system. Close the seacock and remove
the anticorrosion zinc plug from the heat
exchanger.
2. Use a wire brush to remove the loose corrosion on
the anticorrosion zinc plug. Replace the plug when
less than 50% of the 9 mm (11/32 in.) dia. by 19 mm
(3/4 in.) length of zinc remains. See Figure 3-10.
1
2
1. 9 mm (11/32 in.) diameter
2. 19 mm (3/4 in.)
TP-5399-3
Figure 3-10 Anticorrosion Zinc Anode
3. Clean the threaded hole of the heat exchanger and
coat the threads of the anticorrosion zinc plug with
pipe sealant suitable for marine applications.
Install the anticorrosion zinc plug into the heat
exchanger.
4. Open the seacock. Start the generator set and
check for leaks at the anticorrosion zinc plug
location. Check for seawater flow by observing
water discharge from the exhaust outlet.
3.5.4 Pressure Cap
Closed/heat exchanger systems incorporate a
pressurized cap to raise the boiling point of the coolant
and make use of higher operating temperatures. If the
cap leaks, replace it with the same rating type of cap.
Thepressurecapratingis96kPa(14psi).