DIESEL TANK GAUGE NOT WORKING - HOW MUCH DIESEL DO I HAVE?

Oct 8, 2023
29
Hunter 30 Lake Travis, Austin Texas
Stupid question, but I don't trust the fuel gauge on my 30' Cherubini as it has always registered 100% full since I've owned it for the last year. How do I verify the amount of diesel in the tank? I've probably run the engine no more than 10 hours.
 
Jan 1, 2006
7,314
Slickcraft 26 Sailfish
On my Ranger 29 the fuel tank was below the cockpit. I used a dowel pushed thru the fill opening to the bottom of the tank. Where it was wet was the amount of gas in the tank.
 
Sep 25, 2008
7,229
Alden 50 Sarasota, Florida
On my Ranger 29 the fuel tank was below the cockpit. I used a dowel pushed thru the fill opening to the bottom of the tank. Where it was wet was the amount of gas in the tank.
“Sticking the tank” is the typical method of determining the level. The tank dimensions will provide volume. Actual fuel amount can then be calculated. Therefore, you don‘t need to fill it up to find the answer. And with the engine's consumption spec, you then know how much run time you have.
 
  • Like
Likes: Moondawg
Oct 8, 2023
29
Hunter 30 Lake Travis, Austin Texas
“Sticking the tank” is the typical method of determining the level. The tank dimensions will provide volume. Actual fuel amount can then be calculated. Therefore, you don‘t need to fill it up to find the answer. And with the engine's consumption spec, you then know how much run time you have.
Thanks guys.....will do.
 
May 17, 2004
5,369
Beneteau Oceanis 37 Havre de Grace
Also listen to the fill tube as you add the diesel. The tone will change when fuel gets to the top of the tank. There are also custom made vent whistles to make the change more noticeable, but I’ve always just done it by ear. Once you’ve done that a couple times to measure engine hours vs gallons used you’ll be able to judge how much to take better than most gauges.