Most outboard motors are at their most fuel-efficient in the cruise range, roughly 60 to 80 percent of full throttle, rather than wide open.
Beyond running at a moderate speed, focus on maintaining the engine on schedule, using the right propeller, keeping the boat light, and not idling for long stretches.
A clogged fuel filter is another common culprit; you will notice it when you throttle up and the engine cannot draw enough fuel from the tank. Suzuki calls for the low-pressure fuel filter to be inspected at every 100-hour service and replaced every 400 hours or 2 years.
Key Ways to Improve Outboard Fuel Efficiency
- Regular maintenance: routine tune-ups and fixing engine issues before they cost you fuel
- The right propeller: correct diameter and pitch for your boat and engine combination
- Monitor fuel consumption: track your fuel use to see which habits are costing you
- Reduce weight on board: remove gear you do not need for the trip
- Avoid excess idling
Propeller
Use the propeller that best suits your boat and style of boating. Propeller size and pitch have a large effect on fuel efficiency. Too much pitch overloads the motor and keeps it below its rated RPM range; too little lets it over-rev, which wastes fuel and can damage the engine. The test is simple: at wide-open throttle with a normal load, the tachometer should sit inside the range Suzuki publishes for your model. Our full-throttle RPM range and propeller guide lists those ranges and explains how to change pitch, and the Suzuki propeller chart shows what fits each motor.
You can browse our Suzuki genuine propellers, and if you have questions, call us at 561-562-6441 and we can help you choose.
Fuel and Oil
Use fresh, clean fuel. Stale or contaminated gasoline does not burn as well as fresh fuel, and water or phase-separated ethanol in the tank costs power before it costs you a fuel pump. Suzuki specifies a minimum of 87 octane ((R+M)/2), recommends alcohol-free gasoline whenever possible, and allows no more than 10 percent ethanol; higher octane buys nothing on these motors. When you have the choice at the pump, pick ethanol-free fuel (sold as REC-90) over E10, especially for a motor that sits between trips. Our Suzuki outboard fuel requirements page covers the details.
The same holds for oil: a cheap, low-quality oil can foul spark plugs and leave deposits. Use an oil that meets Suzuki's spec (SAE 10W-40, NMMA FC-W rated); Suzuki ECSTAR 10W-40 does. Keep the engine tuned and replace the spark plugs, fuel filters and other wear items on schedule (the spark plug chart lists the plug and gap for each model). A dose of Suzuki Fuel Conditioner & Water Remover helps keep the fuel system clean. Our oil change kits, maintenance kits and engine maintenance parts cover the rest.
Service Schedule
Check your owner’s manual for the recommended service schedule. The three major milestones are the initial 20-hour service, then every 100 hours and every 200 hours; our maintenance schedule explained lists what is done at each. If you don’t feel comfortable servicing the outboard yourself, call us at 561-562-6441 or email support@boatmaxonline.com and we can point you to the right parts and a dealer.