TP-6137 5/03 35Section 6 Cooling System
6.5 Anticorrosion Zinc Anode
The generator set includes an anticorrosion zinc anode
(plug) to prevent electrolytic corrosion by seawater.
Check and replace the anticorrosion zinc anode at
intervals recommended in the service schedule.
Depending upon operating conditions and seawater
properties, the anticorrosion zinc anode may require
more frequent replacement. See Figure 6-7 for the
location and use the following procedure.
TP-6134
1. Seawater pump
2. Water-cooled alternator
3. Anticorrosion zinc anode (seawater drain)
1
2
3
Figure 6-7 Anticorrosion Zinc Anode
Anticorrosion Zinc Anode Replacement
1. With the generator set cooled, close the seacock,
open the petcock on the engine, and drain the
coolant into a suitable container.
2. Remove the anticorrosion zinc anode (plug).
3. Use a wire brush to remove the loose corrosion on
the anticorrosion zinc anode. Replace the anode
according to Figure 6-8 and Figure 6-9.
Anticorrosion Zinc Anode Replacement
New Anode
Dimensions mm (in.)
Replace When Percent
of Zinc Remaining Is:
10 (0.39) x 20 (0.79)
<50% of
length/diameter
Figure 6-8 Anticorrosion Zinc Anode (Plug)
Measurements
TP-5586-3
1
2
1. Diameter: 9.5 mm (0.375 in.)
2. Length: 19.05 mm (0.75 in.)
Figure 6-9 Anticorrosion Zinc Anode (Plug)
4. If necessary, cut the anticorrosion zinc to the
correct length. Clean the threaded hole of the
engine and coat the threads of the anticorrosion
zinc anode (plug) with pipe sealant suitable for
marine applications. Install the anticorrosion zinc
anode into the threaded hole.
5. Close the petcock on the engine and open the
seacock.
6. Refill the seawater cooling system.
7. Start the generator set and check for leaks at the
anticorrosion zinc anode location. The pump is
operating if the cooling water flows from the
exhaust outlet. If water is not discharging at the
exhaust outlet, see Section 2, Prestart Checklist,
Seawater Pump Priming in the operation manual.