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Printed in U.S.A. -
2004, Mercury Marine
90-10209050 JANUARY 2004
INSTALLATION MANUAL
75/90/115 OPTIMAX
Important Information
1
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Electric Fuel Pump
1
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Boat Horsepower Capacity
2
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Start in Gear Protection
2
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Selecting Accessories For The Outboard
2
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Fuel Tank Installation
2
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Installation Specifications
3
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Lifting Outboard
3
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Steering Cable
4
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Steering Link Rod
5
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Determining Recommended Outboard Mounting
Height
6
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Installing Outboard
7
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Electrical, Fuel Hose and Control Cables
8
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Front Cover Assembly
8
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Remote Wiring Harness
9
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Battery Cable Connections
10
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Fuel Hose Connection
11
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Shift Cable Installation
12
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Throttle Cable Installation
14
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Filling Fuel System
15
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Filling the Oil Injection Tank
15
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Priming the Oil Injection Pump
16
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Propeller Installation
17
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Trim-In Stop Adjustment
18
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NOTICE TO INSTALLER: After completing assembly, these instructions should be
placed with the product for the owner’s future use.
IMPORTANT: If the boat is to be water tested, the operator should be familiar with the
operation procedures in the Operation and Maintenance Manual.
Important Information
Before Starting Engine
Before starting engine for the first time, prime the oil injection pump. Procedure on page 16.
CAUTION
Prevent possible engine damage, Prime the oil injection pump before starting en-
gine for the first time.
Required Fuel
Do not use pre-mixed gas and oil in this engine. Use a clean and fresh recommended
gasoline during engine break-in and after engine break-in.
Recommended Oil
Mercury or Quicksilver Optimax/DFI 2-Cycle engine oil is recommended for your engine. If Opti-
max/DFI 2-Cycle engine oil is not available, we recommend using Mercury or Quicksilver TC-W3
Premium Plus 2-Cycle Oil. Severe engine damage may result from use of an inferior oil.
Avoiding Fuel Flow Restrictions
IMPORTANT: Adding components to the fuel supply system as in filters, valves, fit-
tings, etc. may restrict the fuel flow and could cause engine stalling at low speed, and/
or a lean fuel condition at high RPM, that could cause engine damage.
Electric Fuel Pump
If an electric fuel pump is used, the fuel pressure must not exceed 4 psig at the engine. If
necessary, install a pressure regulator to regulate the pressure.