gas gauge

[Rice Fisher]

Long time reader, first time poster.<br /><br />I have a '99 Fisher Avenger Sport Pro (17'). My question is does the gas gauge on boats normally read accurate sitting still or while moving?<br /><br />I read under an eighth of a tank sitting still, but 3/4 at wot. I filled it up and it took 10 gallons - not sure the size of the tank - been told 30 gallons, but don't want to find out in the middle of the lake.<br /><br />thanks

 

[rickdb1boat]

Re: gas gauge

Should not be that much difference in the readings from sitting still and moving. Sending unit is improperly installed or is defective. None of them are perfect, anyway. But they do give an indication of what you have in the tank. Just have to get used to it..

 

[markvan]

Re: gas gauge

Rice Fisher - mine was doing that - it would have a difference of about 1/2 a tank or so depending if I was at WOT or sitting still. I had a look at the sending unit and notice that float on the end of the arm would pivot forwards and backwards (front of the boat to back) I turned the sending unit 90 degrees so that it now moves side to side and problem solved it now always reads the same thing.

 

[Chinewalker]

Re: gas gauge

NEVER implicitly trust a boat's gas gauge. I have VERY rarely seen a marine fuel gauge that was dead on all the time. Matter of fact, I don't think I've ever seen one. I take that back. The ONLY fuel gauge I will trust is a yard stick stuck in the fuel filler with the boat at a dead stop. Of course, this is likely impossible on most boats, as the fuel filler to tank is rarely a straight shot. The fiberglass tanks with the clear sightline on the side are usually pretty good, too. Other than those, use the gas gauge as a reference only. If it's bobbing around, then you've got some fuel in the tank. If it normally bobs around and suddenly it DOESN'T - then you're on the low end. <br /><br />You can figure out a ballpark idea of your tank's volume by doing some measurements - length/width/depth etc. and then converting to gallons. One cubic foot holds about 7.5 gallons. A fuel meter can tell you exactly how much you've used and go from there...<br />- Scott

 

[Solittle]

Re: gas gauge

The easiest way to determine the capacity of the tank is to borrow a 6 gal tank, run the main dry, use the 6 gal to get home and then fill the main.

 

[cp]

Re: gas gauge

According to the below link, a 2003 model of your boat has 30 gallon fuel tank capacity.<br /><br />Fisher 170 Pro Avenger Sport

 

[sunedog]

Re: gas gauge

The shape of the tank also has a big impact on the gauge. I had a 19' Regal Valanti bow rider and the tank was very shallow. It was about 6 or 8 inches deep. (Obviously, it was fairly long and wide, but shallow.) The float arm didn't move much going from full to empty so the gauge was not particularly useful.