Not every one is a mechanic/electrician nor are all folks mechanically/electrically inclined. But... If you own a boat with a fixed fuel tank sooner or later - you'll be wondering why the fuel gauge isn't working. My intent here is to provide some links that unwrap the fuel gauge/sending unit mystery and provide some basic trouble shooting skills to assist in resolving fuel gauge problems.
For a basic understanding of exactly how a fuel gauge works go here:
http://auto.howstuffworks.com/fuel-gauge.htm
If you read through all the pages you'll come away with a basic knowledge of how the fuel gauge/sending unit work together to provide the basic information "How much fuel is in the tank"
Later I will add to this same post providing photos, how to find that stinkin' sending unit, and some cheap, quick, easy ways to diagnose the problem. It's a relatively simple process once you accept you're only dealing with 3 compontents 1.) the gauge, 2.) the sending unit 3.) the wires connecting the two. If you don't have a problem with at least one of those three - you don't have a fuel gauge problem.
Have you ever wondered "why" the fuel gauge doesn't bounce around all over the place when you know fuel is sloshing every which way in the tank while you're navigating rough water??? Look at the diagram on page two and you'll see a heating element adjacent to the gauge - it's not instaneous and takes a second or to to respond to the input from the sending unit. There is a "play" button right above the box that puts the system in motion, click on that play button and you'll get an idea of why the needle on the gauge doesn't jump around.
Is it the gauge? Is it the sending unit? Is it the wiring? What if it's two out of 3??? Stay tuned and I'll be discussing the sequence and order of testing to figure that out.
For a basic understanding of exactly how a fuel gauge works go here:
http://auto.howstuffworks.com/fuel-gauge.htm
If you read through all the pages you'll come away with a basic knowledge of how the fuel gauge/sending unit work together to provide the basic information "How much fuel is in the tank"
Later I will add to this same post providing photos, how to find that stinkin' sending unit, and some cheap, quick, easy ways to diagnose the problem. It's a relatively simple process once you accept you're only dealing with 3 compontents 1.) the gauge, 2.) the sending unit 3.) the wires connecting the two. If you don't have a problem with at least one of those three - you don't have a fuel gauge problem.
Have you ever wondered "why" the fuel gauge doesn't bounce around all over the place when you know fuel is sloshing every which way in the tank while you're navigating rough water??? Look at the diagram on page two and you'll see a heating element adjacent to the gauge - it's not instaneous and takes a second or to to respond to the input from the sending unit. There is a "play" button right above the box that puts the system in motion, click on that play button and you'll get an idea of why the needle on the gauge doesn't jump around.
Is it the gauge? Is it the sending unit? Is it the wiring? What if it's two out of 3??? Stay tuned and I'll be discussing the sequence and order of testing to figure that out.
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