Download it here. The app is searchable in the Google Play Store under Sailboat Owners.
Sorry iPhone/iPad users, we are still waiting on Apple. :(Click the X in the upper right corner to make this go away
Yep…that works too…An "hour meter" Every engine independent of the boat, weather, loads has a "Burn Rate" as the fuel it burns in gallons in one hour at a set RPM. If you know the size of your fuel tank and how many hours you have ran since last fill up you will know how much fuel you have used and how much fuel is left in the tank. This method of measuring fuel in the tank has been used for many decades by professional and amateur mariners because it yields more accurate results and more useful information than the usual tank gauges sold in the market.
First you install an electrical hour meter powered form the On/Off key switch. This will insure that hour meter only runs when the switch is On while the engine runs. Unlikely the switch will be left On with the engine Off because of the racket made by the oil pressure buzzer alarm.
Second, calculate your engine's Burn Rate. The formula BR=gallons x hour. Just those two variables nothing else. The rule of "good enough results" is applied to use averages and approximations so that simple calculations can be made in the head without altering the information that we need as a result. (how much fuel we have left and do I have enough to get me where I want to go) The first approximation we use is Average Burn Rate, this allows for you to operate your boat under power as you customarily do. It is surprisingly how time after time you will have used a similar amount of fuel without having to account for RPM changes. To establish this Average Burn Rate you fill your tank to full and then run the boat for 6 to 8 hours , not necessarily consecutive. Then you proceed to top the fuel tank again and take notice of the fuel pump reading of the number of gallons taken or used however you want to call them. Divide the number of gallons by the number of hours in the hour meter and that will give you the ABR. Over the years it has been observed that up to 10HP engines will burn under 1/4 GPH, a 20HP under 1/2 GPH, a 30 HP 3/4 GPH you get the picture and to be on the safe side round up your horsepower to the largest number. This is only a guide to be used in absence of a well calculated ABR.
Third, the size of your fuel tank. It is worth knowing that amount of usable fuel is less than the listed capacity in the boat specs. That is because the engine will start sucking air and quit before all the fuel is utilized. To account for this and to provide an adequate reserve for emergencies we reduce the usable fuel capacity by 20%. You will see how this is prudent when we start calculation range.
Fourth, this component is the heart of the method. Start a log composed of;
DATE write the date every time you top of the tank.
Gallons Used: Write down the number of gallons
Hour Meter Reading: The Hour Meter does not reset so you must write down the reading to be able to calculate the hours at each fuel tank topping even.
Hours since the previous reading: this will the time in hours used for your calculations.
Average Burn Rate; Calculate your ABR and compare to other dates. Each time it will be different but it does not matter as by eliminating the Highs and the Lows yopu will narrow down your true ABR.
Now to simplify the calculations in hour heads we use whole numbers, an ABR of 0.487 will be taken as 1/2. Hours will be rounded to the next 1/2 hour. So lets say you are boarding the boat today and do not remember how much fuel you have left. Take a glance at your hour meter and substract the last reading on the log. lets say it came out to 8 hrs. you know your ABR is close to 1/2 so you can tell you used 4 gallons and have so many left.
I like to test my figures and when I go to top off my fuel tank I will predict the number of gallons I'm going to take. I have never ran out of fuel since I started using the system and usually I'm not more than 1/4 of a gallon off. These are "good enough" results.
Now that you know how much usable fuel you got left, you can calculate how far you can go. Range is influenced by speed and speed is influenced by wind , currents and condition of the hull. You need a speed measuring device. When on a trip I'm just interested in speed over the bottom so I will use a GPS reading. If I can only go 4 knots and I have 20 gallons left I know I can go 80nm before entering the reserve. As conditions can vary during a trip take a speed reading each hour and adjust your range accordingly from that point on recalculating fuel left and distance according to new speed.
Maintaining the log and practicing the calculations will make it almost 2nd nature to be able to accurately know your fuel status at any time.
Thanks GregI don’t know your boat, but I found one of these on the fuel tank of my 1988 O’Day 322…
View attachment 196483
it has a visible gauge (very hard to read on my boat), but I learned it would also drive a standard fuel gauge…
Something like this..
Amazon.com: SAMDO Marine Fuel Gauge Fuel Level Gauge 0-190ohm Signal 52mm with Backlight 12V/24V White : AutomotiveBuy SAMDO Marine Fuel Gauge Fuel Level Gauge 0-190ohm Signal 52mm with Backlight 12V/24V White: Fuel - Amazon.com ✓ FREE DELIVERY possible on eligible purchaseswww.amazon.com
So, you might want to inspect the top of the tank for something similar.
In my experience with fuel gauges I did not find that a peek was enough, I would peek and then tap it and if I got a different level I would repeat the tapping and peeking process again and at the end remain uncertain of how much fuel I had. Never knew when they were stuck or suffered a voltage drop. I guess they are OK for day sails close to fuel sources. An inspection port and a stick or a visual window would be best but not as quick, nor more reliable than a quick glance at the hour meter and some mental calculations. I like being able to calculate on the fly how many nautical miles I can travel before having to refuel.Yep…that works too…
…but a peek at the fuel gauge is way faster
Excellent point…I am primarily a day sailor, running engine 15 minutes in and15 minutes out of my marina. Seldom do I motor any long distances (maybe 5 miles from time time to time).In my experience with fuel gauges I did not find that a peek was enough, I would peek and then tap it and if I got a different level I would repeat the tapping and peeking process again and at the end remain uncertain of how much fuel I had. Never knew when they were stuck or suffered a voltage drop. I guess they are OK for day sails close to fuel sources. An inspection port and a stick or a visual window would be best but not as quick, nor more reliable than a quick glance at the hour meter and some mental calculations. I like being able to calculate on the fly how many nautical miles I can travel before having to refuel.
Same here.Excellent point…I am primarily a day sailor, running engine 15 minutes in and15 minutes out of my marina. Seldom do I motor any long distances (maybe 5 miles from time time to time)