1986 Gas Tank Sending Unit

[11555wally]

I've recently purchased a 86 SB C10. When I picked it up it showed it had 1/2 tank of gas in it. When I got home after 60 miles of driving it was on empty. I put 5 gallons of gas in it and it didn't raise the needle hardly at all. What would be the likely culprit? I've read a few posts on testing these with a multi-meter which I don't have but I was wondering if there is somewhere I could take it to be tested, or does it have to be on the vehicle to be tested. I have the bed off and plan on taking the gas tank down for cleaning and painting. I suppose I could buy a cheap multi-meter and test it myself if I knew how. Thanks for any suggestions

[pontgta]

make sure you have a good ground. If you have the bed off should be easy to pull out sender and test it by moving it.... I do not know what the ohms should be but... With it out move all the way up and the guage should move or have different resistance. Remember to move it slowly to see if it moves and were it stops reading.....also grounding it out i think shoul peg it to full.

[11555wally]

I'll still have to drop the tank as the sending unit is under the cab. By moving the lever up and down and the gauge does not change would that definitely mean that it is the sending unit or the ground or could it still be the gauge. You mention grounding out the sending unit too, would that just be running a jumper from the electric connection on the sending unit to the frame. Would that not blow a fuse or isn't that fuse protected? I'll first make sure I have a good ground to the sending unit. Thanks for the info.

[pontgta]

Yes but the sending unit should be grounded . You have 2 wires ... None of them should have voltage. Its a ground and a sending unit wire directly to the guage. No dual tanks right? If not the wires would go there first

[11555wally]

Just one tank on the drivers side.