Before you start
Gather the appropriate supplies and review the specific equipment manual.
- Tank capacity
- Engine fuel log
- Current and weather forecast
Step-by-step instructions
Determine usable fuel
Published tank capacity may not equal safely usable volume when sloshing, contamination and unpumpable fuel are considered.
Measure actual consumption
Use reliable refill records and engine hours at the RPM and conditions normally used.
Estimate range from speed
Multiply expected hours at the chosen consumption rate by a realistic speed through the water, with allowance for current.
Protect a reserve
Include weather delays, headwinds, harbor maneuvers and an operational reserve based on voyage risk.
Verify on shorter passages
Compare estimates against real fuel use and improve the log instead of trusting one trial.
Safety note
Do not run fuel tanks dry offshore; engine stoppage and air entry can create a dangerous situation.
Key takeaway
Motoring range is determined by usable fuel, measured burn and conservative speed assumptions.
Keep this job on your maintenance schedule
Save the topic as a maintenance task, choose a due date or engine-hour target, and record future service. Free and stored on your device.
Add to my maintenance plannerThis guide is for general education. Follow your equipment manufacturer’s instructions, current navigation guidance and applicable marine safety standards. When uncertain, use a qualified marine professional.