Another Fuel Gauge Question

LUNDINROOF

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I’m trying to fix a few things on my 246G in order to sell it. I put it in my warehouse last November when I bought my 283 and I cannot remember how much gas is in my two tanks. I noticed today that when I check the fuel gauge, both tanks indicate full and it just isn’t likely that they are, I think something must be wrong.

With two different senders, if both went bad at the same time it would be a coincidence, and I do not believe in coincidences. If the switch was bad, neither tank would register??

Could this be a bad gauge?

Only way to tell is to run the boat for a while and see if either tank indicates less than full.

Thanks for any suggestions.
 

NOTHING ELSE MATTERS

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Shut down your batteries, disconnect the sender wire from the sender, should be pink, then reconnect the wire power up the batteries and see if the gauge reads O.K now. It worked for me once, don't ask why cause there is no explanation for it.
 

seabob4

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Lundinroof,
If you have a bad ground on a fuel sender, it will peg the gauge to full. Check for ground continuity on both tanks to a known good ground, also for continuity on the ground on the gauge...
 

seasick

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seabob4 said:
Lundinroof,
If you have a bad ground on a fuel sender, it will peg the gauge to full. Check for ground continuity on both tanks to a known good ground, also for continuity on the ground on the gauge...

If you have no ground, the gauge will read EMPTY.
 

seabob4

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seasick said:
seabob4 said:
Lundinroof,
If you have a bad ground on a fuel sender, it will peg the gauge to full. Check for ground continuity on both tanks to a known good ground, also for continuity on the ground on the gauge...

If you have no ground, the gauge will read EMPTY.

A known "good" ground, when touched to the sending wire, will cause the gauge(s) to peg to full. A faulty ground, i.e. one that is not making the best contact, can do the same as the return path seeks to find it's way back to the batts. That return path can include the "positive" side of the 12V circle, hence the same reaction as touching a known "good" ground to the sender wire...pegging the gauge full...
 

seasick

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seabob4 said:
seasick said:
seabob4 said:
Lundinroof,
If you have a bad ground on a fuel sender, it will peg the gauge to full. Check for ground continuity on both tanks to a known good ground, also for continuity on the ground on the gauge...

If you have no ground, the gauge will read EMPTY.

A known "good" ground, when touched to the sending wire, will cause the gauge(s) to peg to full. A faulty ground, i.e. one that is not making the best contact, can do the same as the return path seeks to find it's way back to the batts. That return path can include the "positive" side of the 12V circle, hence the same reaction as touching a known "good" ground to the sender wire...pegging the gauge full...

I don't think so. A normal American sender will present 30 ohms at full and about 230 at empty. No ground looks like infinite ohms or above 230 so, the guage reads empty. A short to ground reads zero ohms, well above 30 and results in a reading of Full. A bad ground will be somewhere in between but since whatever it is, it adds ohms to the reading and that pushes the gauge towards empty.
 

LUNDINROOF

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I think you guys are trying to confuse an old man, and you seem to be succeeding. Both statements seem to indicate that the problem may be in the ground. So, I ran a wire from the grounding lug on the tank directly to the negative pole of the battery. Same thing, the needle pegs to full. Maybe both tanks are full, I will have to wait until Memorial Day to try and run some gas through it and see if either needle drops.
I’ll let you know.
 

BobP

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If you are a DIYer, go to wemausa.com (or is it wema.com(?)), they have a troubleshooting guide.
 

seasick

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LUNDINROOF said:
I think you guys are trying to confuse an old man, and you seem to be succeeding. Both statements seem to indicate that the problem may be in the ground. So, I ran a wire from the grounding lug on the tank directly to the negative pole of the battery. Same thing, the needle pegs to full. Maybe both tanks are full, I will have to wait until Memorial Day to try and run some gas through it and see if either needle drops.
I’ll let you know.
I hope the tanks are not full of water....