18

The Cal 27 is a classic American fiberglass cruiser-racer sailboat designed by C. William Lapworth and built across multiple distinct generations by Jensen Marine (Cal Yachts) starting in 1971. [1, 2]

The total fuel range for a Cal 27 with a Yanmar 1GM and a 12-gallon tank is roughly 190 to 300 nautical miles (or about 34 to 54 hours of motoring time), depending on your throttle setting and sea conditions. [1]

Engine and Consumption Details

• Fuel Burn Rate: The Yanmar 1GM (9 hp single-cylinder diesel) is extremely frugal, burning about 0.22 to 0.35 gallons per hour (GPH) (approx. 0.8 to 1.3 liters per hour) at typical cruising RPM.

• Boat Speed: A

  Cal 27 has a hull speed of around 5.5 to 6 knots, which it can maintain easily under power in calm water. [1, 2]

Estimated Range Breakdown

• Maximum Range (Empty to Full - 12 gallons):

  • At 0.22 GPH = ~54 hours = 300 nautical miles at 5.5 knots.

  • At 0.35 GPH = ~34 hours = 189 nautical miles at 5.5 knots.

• Practical / Safe Range (Keeping a 20% reserve / 9.6 gallons usable):

  • Expect a safe cruising distance of roughly 150 to 180 nautical miles before needing a refill.

#18 has 2 batteries: 1 West Marine lead acid and 1 Napa lead acid.