Bad gas gauge

[jlinder]

A full tank reads 1/4 to 1/2 full, and quickly goes down from there as I burn fuel. I will check the voltage on the gauge, but I suspect the problem is in the sender.<br /><br />Are there any common problems I should look for, or basic repair tips anyone can share?

 

[cc lancer]

Re: Bad gas gauge

When you get the sender out ,you will see a curved metal thing that looks like a old watch band.<br />Don't laugh to hard...take a pencil eraser and clean the curved part.<br />Take a piece of 1500 grit cloth and rub the contact.<br />Hook the 12 volt wire to it and ground the round frame and raise the float up and down. If it does not read correctly, you may have to bend the contact down to where it rubs better against the curved band. It should then read correctly.<br />After you have learned how they work, thrown the unit in the trash and go buy a new one. They are usually less than $20.00. And this is not the place to save money.

 

[jlinder]

Re: Bad gas gauge

An exposed electrical contact in a tank of gas? Sounds like a disaster waiting to happen.<br /><br />Where do I find the replacement sender? How standard are they? What info do I need? (Make model of tank, dimensions of tank, etc.)

 

[Boatin Bob]

Re: Bad gas gauge

No there is no 12v wire on a gas tank sender. The sender wire is a ground that changes it's resistance as the sending unit moves in the tank. Your sender could be faulty either mechanically or electrically. You can replace most of them with a generic type that just has to be adjusted for your tank for around $25.

 

[swist]

Re: Bad gas gauge

The float type sensors used in most small boat tanks are borrowed from cars, which bounce around a lot less. They are notoriously inaccurate at best - one reason is that boat tanks usually have baffles which keep the fuel from shifting too fast. Frequently after the sender has been beat up after a couple of years, it will hang up on a baffle, which could give either too high or too low readings.

 

[jlinder]

Re: Bad gas gauge

Are there different designs for replacement senders? If so, which is better?<br /><br />I have seen pictures of senders with their float on an arm. I wonder if there are any better designs?

 

[Boatin Bob]

Re: Bad gas gauge

You are not going to find one that gives you even the accuracy of a car fuel sender (some of these are hundreds of $$$ now) either pull it out and see if it's movement is being restricted or replace it. If you want to get very precise you can buy one of those fuel scan devices that measure how much fuel you are burning. You add in the # of gallons you put in during a fill and then monitor your usage. If you put in 30 gal this will tell you when you've used the 30 gal. Note...these are not cheap either (but what is on a boat )

 

[jlinder]

Re: Bad gas gauge

I had been thinking about something that measures fuel flow to get an accurate picture.<br /><br />I really just want something I can count on. I never plan on having to know how close to empty I am, just want to know that 1/2 is really 1/2 tank.<br /><br />We go out on some pretty big lakes and camp for a couple of days. Never seem to have a marina close by to fill up, and always have a fear that one of us runs the fuel down on day one. Day two we wind up in trouble.

 

[swist]

Re: Bad gas gauge

I can't afford a floscan, but I track the hour meter and I know my average fuel burn in gallons per hour.<br />I always use this info to check against the guage since it's so unreliable. <br /><br />I replaced the sender 3 times in the first 5 years I had the boat - 3 different brands. They are all crap. I'm not asking to spend money, but an "instrument" that costs $19.95 or less can hardly be precision.

 

[Solittle]

Re: Bad gas gauge

I did mine a year ago. I called the tank manufacturer (listed on the data plate on the top of the tank) and got the exact replacement for my tank. I have more confidence in its accuracy since it is specific to my tank than I would be with the generic.

 

[jlinder]

Re: Bad gas gauge

With all the incredibly expensive stuff out there you need for a boat, you can only find cheap senders that don't work.<br /><br />You would have thought that someone would have invented a sender that works and costs a whole $40.

 

[jlinder]

Re: Bad gas gauge

SoLittle,<br /><br />How much did the exact replacement cost you? Just curious what the difference (if any) was.