Fuel Guage and Sending Unit Problems -Update-

[Andrew93]

When I got the boat last fall I remember the previous owner says he thought there was a dead spot in the fuel sending unit. It had a little over a half tank in the main and the aux tank was full, he said he thought the dealer replaced it but it looks original. On the ride to my mooring the fuel gauge lost its connection and never returned on the main tank, it just shows one blinking bar.

Today I uncovered the boat to start working on things and was looking at the connections on the main tank, didn't look great. I tried redoing them and still no connection. I connected the pink wire straight to ground and it showed full so I know the wires to the gauge are ok. I am not very good with an ohms meter but I was getting the same reading from the sending unit and at the switch panel (roughly 55-60). I am leaning towards having to pull the sending unit and replacing if needed but was looking for some advice here first. If I do have to replace does anyone know the model of it?

Thanks

Andrew

 

[Doc Stressor]

Re: Fuel Guage and Sending Unit Problems

You have properly diagnosed your problem as a bad sending unit. This is not uncommon. If you call or e-mail Grady with the model number and year of your boat, they will tell you the proper length of sending unit to use for your replacement. Go with solid state, not a float model, even if you have an older boat that used a float type sender.

 

[Andrew93]

Re: Fuel Guage and Sending Unit Problems

Great, thanks for the info. I just e-mailed Grady for the proper length, hopefully this will take care of the problem!

 

[Firenailer]

Re: Fuel Guage and Sending Unit Problems

I can relate. I put a brand new 208 in last year and 3 months later the fuel gauge was blinking one bar with a full tank.

My Dealer said it would be repaired before I get it back this season.

 

[Andrew93]

Got a new WEMA sender and installed it today. Got the measurement from grady and surprisingly it was 1" shorter than the one I pulled out, but who knows who put that in. Now the gauge works, but the first half of the bars are dead! :bang

Could I have screwed something up, or just coincidence. Seems like too much of a coincidence to me though, even when I switch over to the reserve tank it reads full (which it is) and the first half of the bars are dead.

 

[Tucker]

If you switched sending units and you're still seeing something weird on the gauge than it's the gauge not the sending unit right?

 

[seasick]

Got a new WEMA sender and installed it today. Got the measurement from grady and surprisingly it was 1" shorter than the one I pulled out, but who knows who put that in. Now the gauge works, but the first half of the bars are dead! :bang

Could I have screwed something up, or just coincidence. Seems like too much of a coincidence to me though, even when I switch over to the reserve tank it reads full (which it is) and the first half of the bars are dead.

I believe that hen you turn on the ignition, the gauge goes through a self test. You should see all the bars light up and then go to whatever level it is sensing.

 

[Andrew93]

I think it was the sending unit at first that was not working right because the guage worked fine in the aux 50 gallon tank and all the bars on the gauge showed. Now the gauge is broke and I was wondering if there is anything u could have done switching out sending units or the gauge was just on its way out too. When it goes through its self test the lower half of the bars do not light up, thought I was strange.

 

[grady23]

Did you measure the true depth of the tank? My senders were WEMA and both are 14 inches for main and Aux tanks.

 

[seasick]

I think it was the sending unit at first that was not working right because the guage worked fine in the aux 50 gallon tank and all the bars on the gauge showed. Now the gauge is broke and I was wondering if there is anything u could have done switching out sending units or the gauge was just on its way out too. When it goes through its self test the lower half of the bars do not light up, thought I was strange.

I doubt it was anything you did. I think the display just happened to go bad.

 

[Tucker]

Did you measure the true depth of the tank? My senders were WEMA and both are 14 inches for main and Aux tanks.

Sending units for a Sailfish are definitely different for each tank. The aux tank has a much shorter unit.

 

[dale1]

I had similar problems. I definitive test is;

1. Remove the sending unit.
2. Move the float on the sender up and down slowly to duplicate fuel levels.
3. Watch gauge.

I had a dead spot in the middle section of a sender.

 

[dale1]

https://www.youtube.com/watch?v=Z0K9rAyokn8

 

[seasick]

I had similar problems. I definitive test is;

1. Remove the sending unit.
2. Move the float on the sender up and down slowly to duplicate fuel levels.
3. Watch gauge.

I had a dead spot in the middle section of a sender.

A dead spot, shorted or open sender will not cause the lower bars to go blank. If the bars are blank during self test, the guage is defective

 

[seasick]

Did you measure the true depth of the tank? My senders were WEMA and both are 14 inches for main and Aux tanks.

The sender length should be one inch less than the tank depth measured from the flange to the bottom of the tank. So a 14 inch deep tank would use a 13 inch sender.

 

[grady23]

If you call WEMA they will give you the correct unit but they ask for the depth of each tank