Cooling system flushing is essential to prevent system corrosion and clogging from salt, sand, or other debris. We recommend flushing the cooling system with fresh water after each use as soon as possible. The procedure for flushing the engine in a watercraft is different than most marine engines and must be followed to prevent internal […]
Category: Yamaha Outboard Service Tips
Running In a Bucket -How Deep is Deep Enough?
Have you ever tried running your outboard motor in a tank, barrel, or large bucket? As the photo shows the water pump—specifically the impeller—is located at the top of the gearcase (lower unit), just above the gear housing but below the powerhead/exhaust area. While the pump can sometimes draw water upward if the level is […]
Four Stroke Break In
Motor break-in? Now there’s a loaded question. Ask a group of boaters how to break in a new four-stroke motor and you’ll probably get at least as many different theories as there are people in the group: Boater #1 – Yep, just tie it up to the dock, shift it into gear and let it […]
Power Trim And Tilt (PTT)
Tilt Limiters are available for a variety of models and are designed to help prevent cowling damage when the splash well or other boat components have encroached into the motor area. While the switches are simple devices themselves there are a few points about the system that you should be aware of. • On most […]
Sensor Installation
While installing most new sensors is an easy procedure, a simple mistake can easily damage them. Water pressure sensors are a good example of this. The sensor itself is installed into a large metal body. During sensor installation or removal, if force is applied to the “connector” portion of the sensor instead of the metal […]
Potentiometers
Most people are familiar with the use of potentiometers even if they don’t know them by name. They are a simple form of a voltage divider that can be used in a circuit to send a varying voltage signal that is a fraction of the input voltage. The throttle position sensor (TPS) is one of […]
Metal Gaskets
Many Yamaha motors use metal gaskets between major components, such as cylinder heads and the crankcase, as well as the crankcase-to-upper-casing exhaust guide. Most of these metal gaskets use factory-applied surface coatings and raised ribs to seal between components. There is no need to apply additional sealant when reassembling components. In fact, when additional sealant […]
F2.5A and F2.5B Oil Checking Procedure
There has been some confusion about oil checking procedures for the F2.5A and F2.5B models. Both models have a sight glass to view the oil, but there is an important difference! The sight glass on the port side of the F2.5A block is used to check the oil level. The sight glass on the F2.5B, […]
Yamaha Paint Codes
Yamaha uses coding to signify their paint colors on different parts of their outboard motors. These paint codes are referenced in the chart below, but can often be found in the last two digits of the part number of certain items, for example a lower unit: Note the “8D” code in the part number below. […]
Yamaha Four Stroke Maintenance Schedule
Yamaha recommends service intervals based on “typical” use that includes operating at varied speeds, sufficient time for the engine warm up and cool down, medium to light and average cruising speed near 3000 to 4000 rpm range. If your normal operating conditions are different, more frequent services should be considered, especially engine oil and gear […]