Mercury 135 OptiMax Manual page 75

OUTBOARD INSTALLATION
Dual Outboards
Connect a common ground cable (wire size same as engine battery cables) between negative (–)
terminals on starting batteries.
b
a - Red sleeve - positive (+)
b - Black sleeve - negative (–)
FUEL HOSE AND OIL HOSE CONNECTIONS
Fuel Hose Connection
Fuel Hose Size - Minimum fuel line inside diameter (I.D.) is 8mm (5/16 in.), with separate fuel line/fuel
tank pickup for each engine.
1. Fasten remote fuel hose to fitting with hose clamp.
a
c
(-)
67
a
b
(-)
c - Ground cable
d - Cranking battery
d
d
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