Mercury 135 Pro XS OptiMax Manual page 141

3. If the oil level is less than 118 ml (4 oz), loosen the vent cap.
Use a squirt can and fill the tank with at least 118 ml (4 oz)
of the recommended oil. Tighten the vent cap.
PRIMING THE OIL INJECTION PUMP
Before starting engine for the first time, prime the oil injection
pump. Priming will remove any air that may be in the pump, oil
supply hose, or internal passages.
a
a - Oil injection pump
b - Oil supply hose
IMPORTANT: Fill the engine fuel system with fuel before priming
the oil injection pump. Otherwise, the fuel pump will run without
fuel during the priming process and may be damaged.
Prime the oil injection pump as follows:
1. Fill the engine fuel tank with fuel.
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OUTBOARD INSTALLATION
b
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a - Engine‑mounted oil reservoir
tank
b - Vent cap
a
b
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