Thread:

Fuel Gauge/Sender?

So how do fuel gauges work. My left tank always shows full. I swapped wires at the gauges and the problem moved to right side so I know the gauges are working. I have access to the senders but I dont know what I should be checking for. Power, no power, open, closed, ohms, etc what kind of readings shoulod I be looking for.

You need to pull the senders and check the ohms. Most GM is 90 ohms. Check the ohms with the float down and again with with the float up. If it ranges between 90 ohms (or whatever the sender is rated at) then its good. Also check the wiring to and from the gauge, if there is a bad spot, the gauge will have a false reading.

Do you have 2 senders and 2 gauges, or 2 senders, one gauge and a switch?

2 Gauges and 2 senders. Turns out that the float and arm fell off of the sender. Spent 2 hours trying to fish it out of the tank but no luck. Tomorrow Im going to put some fuel back into the tank so hopefully the float will come up to where I can get to it.

Originally Posted by danfornow1

So how do fuel gauges work. My left tank always shows full. I swapped wires at the gauges and the problem moved to right side so I know the gauges are working. I have access to the senders but I dont know what I should be checking for. Power, no power, open, closed, ohms, etc what kind of readings shoulod I be looking for.

Buddy, please be carefull playing with senders and do not send power to them for testing. Usually we reccomend removing the senser and disconnecting it from the boat, then bench testing it independent for your saftey. Sounds like just a sender though.

Originally Posted by BOOSTPOWER

Buddy, please be carefull playing with senders and do not send power to them for testing. Usually we reccomend removing the senser and disconnecting it from the boat, then bench testing it independent for your saftey. Sounds like just a sender though.

Turns out I probably caused the problem. The boat was bought full of gas and I siphoned it out because I didnt know how old the gas was. When I pulled the sender out, the float and arm where missing. Probably knocked off by me.
Three hours of fishing in the tank and no luck so I filled it back 3/4 full of gas to get the float where I might be able to fish it out. After another half hour of fishing I finally got the float out of the tank.
All back together and working great now.

Some folks will not like my advice: Put in a new sender, and leave that old float in there. It isn't going to hurt anything.

I was literally 2 minutes from bailing out and ordering a new sender when I was finally able to fish it out.