Mercury BRAVO Service Manual

TROUBLESHOOTING SERVICE MANUAL NUMBER 28
Page 1C-30 90-863160 MAY 2000
Corrosion On Underwater Parts, With MerCathode Or Impressed Current
Protection
DRIVE CORRODING
Cause Special Instructions
Poor connection between reference
electrode (BRN) lead or anode
(ORN) lead and MerCathode
controller.
Clean and/or tighten connection.
Repair wiring.
Faulty MerCathode reference
electrode.
Disconnect reference electrode lead
(BRN) from the controller “R”
terminal. Connect the lead to positive
(+) terminal of a digital multi-meter (set
on 0-2000 millivolt scale). Connect
negative (–) meter lead to negative (–)
battery terminal. Note meter reading;
then repeat the test with a test
silver/silver chloride reference
electrode held behind the drive. The
same reading should be obtained in
both cases. If not, replace the
reference electrode.
Faulty MerCathode controller.
With anode and reference electrode
leads connected to controller, connect
a jumper wire between “R” and
negative(–) terminals on controller.
Connect positive (+) lead of volt meter (set
on 0-20 scale) to “A” terminal on controller.
Connect the negative (–) meter lead to the
negative (–) controller terminal. Reading
should be as follows:
D Freshwater Areas = 11.5 volts
minimum
D Seawater Areas = 3.55 volts
minimum
If the reading is low, replace the
controller.
Too much cathode (such as stainless
steel).
MerCathode system overpowered by
large quantity of stainless steel below
the waterline.
Loss of continuity between sterndrive
components and ground.
Ensure continuity (check continuity
wires and washers).
Sacrificial anodes consumed, painted
or inoperative.
Replace anodes.
MerCathode reference electrode or
anode painted.
Remove paint or replace anode or
MerCathode reference electrode.

Mercury BRAVO Specifications

General

Brand	Mercury
Model	BRAVO
Category	Engine
Language	English