Gas gauge not working

cappucho

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Just launched my 2006, 225 Tournament yesterday after being laid up for the Winter. Everything worked fine but the gas gauge shows empty. No bars showing at all even though I know the tank is full. Any suggestion on how to fix this problem would be appreciated. Thanks!
 

DennisG01

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Searching this site and Googling is your friend. There is LOT'S of info on this subject and nothing has changed in decades of diagnosing a boat's fuel gauge.

Basically, you have the sender... the wiring to the gauge... and the actual gauge (and it's power/ground) to check out.

- 12V to the gauge and the ground is good?
- Remove sender wire at the sender and, with key ON, gauge should read empty. Touch the wire to the tank ground and gauge should read full.
- If still nothing, do the same test as above, but at the actual gauge.
- Ohm the sender... with your full tank, it should read approximately 30ohms.

Based on above results, you can narrow down to which of the three culprits is bad.
 

against the wind

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had the same problem. change ur sender about 55 dollars ,and your on your way
 

TonyD

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Yeah, I just started a thread about this very same topic. Just search around the forum - I also found a lot of my research on the internet. WemaUSA also has a great "Tech" page too.

Like Dennis said, you need to troubleshoot the issue. Is it your sending unit? Your gauge? Maybe just a bad ground. My issue ended up being the sending unit. 50 something bucks from Wema and now I am all set.

Good luck!

Tony D.
 

Time and Tide

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I just repaired mine on my 208. It worked intermitently. It read good, then out on the water it would flash one bar. Don't listen to people saying to replace the sending unit tight away. It may be that but perform the diagnostics first. Remove the pink wire going to the gauge. Touch it to the green (ground) wire. Does the tank read full? Possibly sending unit. If it still reads empty, run a direct ground from the battery to the same pink wire. Does it now read full? That means a bad ground. Reconnect the pink wires and run the groun from the battery to the sender/tank ground. If all is good the gauge should tead the correct fuel level. Also, if you know the approximate fuel level in the tank and connect an ohm meter to the two sender leads you will get a reading of between 33 and 240. 33 being a full tank and 240 being about empty. Do the math. 0 = 240 ohms -33 = your full tank. Do the math for between.
Mine was a bad ground where the two green wires are connected to the batteries with the main ground.
My boat does have a WEMA sender.
Hope this helps. Let me know what you find.
 

seasick

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Time and Tide said:
I just repaired mine on my 208. It worked intermitently. It read good, then out on the water it would flash one bar. Don't listen to people saying to replace the sending unit tight away. It may be that but perform the diagnostics first. Remove the pink wire going to the gauge. Touch it to the green (ground) wire. Does the tank read full? Possibly sending unit. If it still reads empty, run a direct ground from the battery to the same pink wire. Does it now read full? That means a bad ground. Reconnect the pink wires and run the groun from the battery to the sender/tank ground. If all is good the gauge should tead the correct fuel level. Also, if you know the approximate fuel level in the tank and connect an ohm meter to the two sender leads you will get a reading of between 33 and 240. 33 being a full tank and 240 being about empty. Do the math. 0 = 240 ohms -33 = your full tank. Do the math for between.
Mine was a bad ground where the two green wires are connected to the batteries with the main ground.
My boat does have a WEMA sender.
Hope this helps. Let me know what you find.

Just curious. Before you went on the water and it flashed one bar, what was on the display? If it was one bar then I can explain how it might flash one bar. Usually the sender gets either stuck at a particular level, reads full (either stuck up high or shorted to ground) or empty (open circuit). The flashing one bar means that a specific resistance was read and that means there was connectivity.
 

Time and Tide

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Seasick,
I understand your thinking but you only semi correct. There was an intermitent ground and it would read proper but when there is no ground on the sender it will read one flashing bar on the gauge. If you completly disconnect the green wire on the sender it will flash one bar. Running a wire fron the sender green or black wire to a known good ground such as the negative side of the battery, the gauge functioned properly.
 

seasick

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Time and Tide said:
Seasick,
I understand your thinking but you only semi correct. There was an intermitent ground and it would read proper but when there is no ground on the sender it will read one flashing bar on the gauge. If you completly disconnect the green wire on the sender it will flash one bar. Running a wire fron the sender green or black wire to a known good ground such as the negative side of the battery, the gauge functioned properly.

You may be right! It now occurs to me that I am not sure what the empty condition display looks like. I thought it was no bars but it may in fact be the one flashing bar.
I guess I was 'wr..g' again:)
 

SC Adventure 208

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I just had to replace my gauge on my 208. It had been replaced 4 years ago with one from Royce Industries. Royce told me that they thought it was the float gone bad and not the sender itself. It is set up so you can replace the float or even the sensor alone (the sensor can be replaced without getting into the tank itself so it was a nice design). I got a new WEMA gauge and when I pulled the Royce gauge out it was in fact the float....if I moved it up the shaft the gas would read full. Nonetheless, I put in the WEMA unit and it's working fine. Royce wanted $25 for a new float....I think they should have sent one or free.
 

Time and Tide

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The float was probably manufactured to eventually go bad so they can sell customers another one (and make more money). That is probably why you can buy it separate.
Glad you replaced yours and it is working properly now.