TP-6252 2/08
40 Section 3 Scheduled Maintenance
3.9.7 Anticorrosion Zinc Anode
The heat exchanger on models 8/9/10EOZD,
6.5/7/9EFOZD, 28/32EOZD, and 23/27EFOZD
contains 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 Section 1 for the
location and use the following procedure.
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) from
the heat exchanger.
3. Use a wire brush to remove the loose corrosion on
the anticorrosion zinc anode. Replace the anode
according to Figure 3-13 and Figure 3-14.
Anticorrosion Zinc Anode Replacement
Models
New Anode
Dimensions mm (in.)
Replace When
Percent of Zinc
Remaining Is:
8/9/10EOZD
6.5/7/9EFOZD
9 (0.34) x 43 (1.7)
<50% of
length/diameter
28/32EOZD
23/27EFOZD
9 (0.34) x 19 (0.75)
<50% of
length/diameter
Figure 3-13
Anticorrosion Zinc Anode (Plug)
Measurements
TP-5586-3
1
2
1. Diameter: 9 mm (0.34 in.)
2. Length: 43 mm (1.7 in.) for 8/9/10EOZD, 6.5/7/9EFOZD models or
19 mm (0.75 in.) for 28/32EOZD, 23/27EFOZD models
Figure 3-14
Anticorrosion Zinc Anode (Plug)
4. Clean the threaded hole of the heat exchanger and
coat the threads of the anticorrosion zinc anode
(plug) with pipe sealant suitable for marine
applications. Cut the anticorrosion zinc to the
correct length. Install the anticorrosion zinc anode
into the heat exchanger.
5. Close the petcock on the engine and open the
seacock. Refill the cooling system.
6. 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 2.1, Prestart
Checklist—Seawater Pump Priming.