Use a standard DVOM to track DC stray current through bilge water and home in on electrically “leaky” devices like
pumps and float switches, and to find active DC positive conductors lying in bilge water. (Reprinted with permission from
Boatowner’s Mechanical and Electrical Manual,third edition, by Nigel Calder)
from batterywater penetrates switch sealwater
in bilgecurrent is fed
from the positive
terminal on theswitch to the
other terminalthrough the
waterA leaking seal on
a float switch will
result in stray-
current corrosion
at the positive
switch terminal.
This will eat the
positive cable off
the terminal,
disabling the
switch and pump.a basic corrosion survey 119