Yamaha F150BET User Manual

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MOUNTING THE OUTBOARD MOTOR
WATER LEVEL GUIDELINE (4-STROKE ENGINES)
If you replaced 2-stroke engine to 4-stroke engine which has the same horse power, a boat tends to
become “stern heavy” because of heavier engine weight.
As a result, water line will rise and get close to the power head.
This causes poor engine performance, and water could easily enter into the cylinder(s) and damage
the engine.
Therefore, you should consider the water level guideline when installing a 4-stroke outboard motor.
When mooring a boat with a maximum boat load, maintain the minimum height (H) shown in the
illustration between the water surface and the clamp bracket seating point.
Minimum height between water surface and bracket seating point
Model Min. height (H)
Carbureted F2 – F60 150 mm 5.9 in
Fuel injected F40 (4-cyl) – F70 100 mm 3.9 in
F75 and above 100 mm 3.9 in
Water surface
(H)

Yamaha F150BET Specifications

General

Compression Ratio	10.0:1
Full Throttle RPM Range	5000 - 6000 RPM
Lubrication System	Wet Sump
Starting System	Electric
Gear Ratio	1.86:1
Gear Shift	F-N-R
Cooling	Water Cooled
Steering	Remote
Engine Type	4-Stroke
Max Output	150 hp
Operating Range	5000 - 6000 rpm
Fuel Induction System	Electronic Fuel Injection (EFI)
Ignition System	TCI (Transistor Controlled Ignition)
Alternator Output	50 Amp
Exhaust	Through Propeller Hub (Jet Prop)
Shaft Length	25 in
Recommended Fuel	Regular unleaded gasoline (minimum 87 octane)