Gas gauge suddenly stopped working

[Capevettes]

My fuel gauge suddenly stopped working this morning. It is reading empty with just over 1/2 tank of fuel. It is a 2000 18 foot Classic with factory gauges. Don't know if it had anything to do with it, but it happened shortly after a "spirited" take off with the bow up in the air at a pretty steep angle (my trim was up a bit). Any trouble shooting hints? Not sure if I'm looking at a gauge, send unit, wiring or ground issue. Does the gauge have a dedicated fuse or in line fuse? When I put the key in the on position the needle moves just a bit but it stays on empty

Thanks for any help.

[mattyboy]

probably a loose connection check all connections on the tank and the gauge . it needs to be worked from the gauge out or the tank in

I would work from the tank in to the gauge

If I could get to the sender lead on the tank side I would remove that wire and ground it that should peg the gauge full if it does it looks like a sender, usually the tank is ground on a metallic tank but test with a known good ground . if the gauge doesn't peg full then the problem is in the gauge or the sender wire to the gauge. then remove the sender lead on the gauge and ground the sender post on the gauge it should peg full if not the problem is the gauge.

[Capevettes]

Thanks for your reply Matty. That gives me a definitive procedure to trouble shoot it. Now if I can fit fit my body under that dash I might be able to get this done. I'll let you know how I make out.

Thanks, Paul

[mattyboy]

one big step I left out the key needs to be on so the gauge cluster has power

[pipnit]

i've had this happen in the past two or three times. each time it happened when i was running hard in choppy water. For me it seemed like the sensor took a hit and was stuck in the E position. Each time, i simply hit a couple good waves and she was back to normal. i havent had that condition now for two or three years

[Tidbart]

Maybe easiest to do is a quick check on the sender. Remove the sender wire from the center terminal, put an ohmmeter from the neg terminal to the send terminal and see what you get for a reading. A half tank of fuel, meaning 20 gals in a 41 gallon tank will yield a reading of about 120 ohms or so. If you read 240 ohms or more, which will tell the gauge to read empty, the sender has failed.

If the sender is good move on to connections and the gauge.

B

[Capevettes]

one big step I left out the key needs to be on so the gauge cluster has power

Yes, I figured that was the case. Thanks.

[Capevettes]

i've had this happen in the past two or three times. each time it happened when i was running hard in choppy water. For me it seemed like the sensor took a hit and was stuck in the E position. Each time, i simply hit a couple good waves and she was back to normal. i havent had that condition now for two or three years

I'm glad to hear that. I am going to take it for a ride in a few minutes and see if that is the case. If not I'll start my trouble shooting.

[Capevettes]

Maybe easiest to do is a quick check on the sender. Remove the sender wire from the center terminal, put an ohmmeter from the neg terminal to the send terminal and see what you get for a reading. A half tank of fuel, meaning 20 gals in a 41 gallon tank will yield a reading of about 120 ohms or so. If you read 240 ohms or more, which will tell the gauge to read empty, the sender has failed.

If the sender is good move on to connections and the gauge.

B

Thanks for that info. I am going to take a quick blast around the lake and hope it straightens itself out. I know, wishful thinking. Then I'm on to the trouble shooting.

Oh, the good news...My youngest daughter just started dating a Marine mechanic that knows Donzis. He's coming over later tonight. I know he will fit under there. I really don't!!!

[Capevettes]

i've had this happen in the past two or three times. each time it happened when i was running hard in choppy water. For me it seemed like the sensor took a hit and was stuck in the E position. Each time, i simply hit a couple good waves and she was back to normal. i havent had that condition now for two or three years

Well I just got back from a nice blast around the lake. About 1/2 way through my ride, after accelerating, the gauge started working normally. Even though I did tighten what felt like a slightly loose connection on the gauge I have a feeling the float/send unit was just stuck. Whatever it was is fixed for now.

So all is right with the world

Thanks for the feedback from everyone. Now I can enjoy my sunrise cruise tomorrow without staring at the gauge

[pipnit]

Hey Hey, thats great news. Hopefully you have the same luck I did and it doesnt come up again!

[mattyboy]

I was thinking last night . when we replaced the tank in the 72 cig last year the new tank had the type of sender that measured pressure in the tube it had no float when we first filled it it read empty. we were told that it takes some time for the air pocket in the tube to work itself out and read the pressure of the fuel. I wonder if this is what is happening after going airborne the sender is getting an air pocket that eventually works itself out?

[Capevettes]

That may be the answer Matty. I'm not sure what type of sender a 2000 18 comes with. It worked fine again this morning. Hopefully it continues working.

[mattyboy]

the older type senders had a float on an arm that moved up and down with the fuel level . the newer senders are just a tube and the tube measures the fuel level by the pressure of the fuel being forced up the tube

[Capevettes]

So I take it that my 2000 is the newer style? Kind of makes sense now.