This repair manual covers 1998-2002 Mercury Mariner outboard 2.5-60 HP 2-stroke outboard motors, including:
Book Excerpt: 1998-2002 Mercury Mariner 2.5-60 HP 2-Stroke Repair and Service Manual
- 2.5 HP, 3.3 HP, 4 HP, 5 HP, 6 HP, 8 HP, 9.9 HP
- 15 HP
- 20 HP, 20 Jet, 25 HP
- 30 HP, 30 Jet
- 40 HP, 45 Jet
- 50 HP
- 60 HP
GEARCASE: GEAR HOUSING
REMOVAL/INSTALLATION (2.5 HP MODELS)
OIL INJECTION SYSTEMS
The water pump can be serviced without gear housing removal on 2.5 hp models. Refer to Water Pump in this chapter.
The square drive shaft runs inside a removable support tube in the drive shaft housing. The tube must seal into the lower crankshaft seal.
- Disconnect and ground the spark plug lead to the power head to prevent accidental starting.
- Close the fuel shutoff valve.
- Tilt the outboard to the fully up position.
- Remove the upper mounting bolt, lockwasher and flat washer at the leading edge of the gearcase, and the lower mounting bolt, lockwasher and flat washer directly above the propeller. Then pull the gear housing from the drive shaft housing and place the gearcase on a clean workbench.
- If the square drive shaft and support tube does not come out with the gearcase, remove the drive shaft and support tube from the drive shaft housing.
- Remove the water tube seal from the gearcase.
- To install the gearcase, tilt the outboard to the fully up position.
All models are lubricated by mixing oil with the gasoline. On models that are not oil-injected, the oil and gasoline are premixed in the fuel tank(s) by the boat operator.
The recommended fuel/oil mixture for normal operation in all models without oil-injection is 50 parts of fuel to 1 part of oil (50:1). For 6 gal. (22.7L) of fuel, add one pint (16 fl. oz. (473 mL) of oil
On oil-injected models, the oil automatically mixes with the gasoline. An engine-mounted oil pump injects oil into the fuel pump inlet line. All oil-injected models are equipped with a variable-ration oil-injection pump.
The fuel/oil ration changes with throttle position. At wide-open throttle the fuel/oil ratio is approximately 50-60:1, while at idle speeds the ratio is approximately 80-100:1.
The engine components are lubricated as the fuel and oil mixture passes through the crankcases and into the combustion chambers. The fuel/oil ratio required by the engine varies with engine load and speed. Oil demands are always highest at wide-open throttle.
Subject: 1998, 1999, 2000, 2001, 2004 Mercury Mariner 2.5-60 HP 2-Stroke service, maintenance, repair. ISBN-10: 0892877855 | ISBN-13: 9780892877850