OM3-80 12/21
Lubrication & Maintenance/250 Hour/6 Month (Continued)
RG19661,00003D5 -19-29JAN13-1/2
RG19661,00003D5 -19-29JAN13-2/2
Inspect and Replacing Zinc Plugs
Two zinc plugs (A) are installed in the sea water cooling
system to help reduce the corrosive action of salt in the
sea water. The reaction of the zinc to sea water causes
the plugs to deteriorate, instead of the more critical
cooling system parts. Therefore, the zinc plugs MUST BE
inspected every 250 Hours.
NOTE: Zinc plugs are located in each heat exchanger end
cap and are mounted on hex-head pipe plug.
1. Remove zinc rod from each end cap (B) and observe
condition of each.
apart when tapped, install a new zinc plug.
A—Zinc Plugs
B—End Cap
RG2213
7—
UN—06DEC12
Inspect Zinc Plugs - 4 Cylinder
RG2204
8—
UN—29NOV12
Inspect Zinc Plugs - 6 Cylinder
3. Measure zinc plugs (A) to determine the amount of
erosion on length (B) and outer diameter (C).
If length is less than 15.9 mm (0.63 in.) or outer diameter
is less than 4.8 mm (0.19 in.) on either plug, replace all
zinc plugs.
NOTE: Zinc plug new part dimensions are 31.8 mm (1.25
in.) long and 9.5 mm (0.38 in.) outer diameter.
A—Measure Zinc Plugs
B—Measure Length
C—Measure Diameter
RG6007
—UN—27JAN9
2
Zinc Plug Erosion
29
