Determining a stuck fuel sender from outside the truck

[ml68nova]

A quick question and maybe a stupid one as well,

I have a 72 c30 dually wrecker and my gauge is staying a 1/4 tank but moves at 1/16 either way when using or filling the tank. It just happend last week while towing my car.

I supect the float is stuck or heavy (has a crack) But I would like to check it before taking out the seat (solid will not fold) and yada yada.

Has anyone used a rod through the filler neck to move the float? I noticed from pictures ,the sender is located more to the passenger side possablly making this idea a mute point.

Thanks,Mark

[see ten]

Mine did exactly the same thing for a couple days and then suddenly started working again. I suspect a sending unit is in my future . The filler goes in at an angle so it's going to be difficult to run anything straight through it. I would think a good sturdy coat hanger might be able to be used to bump the float? Who knows? Keep us updated!

[Premium72]

pulling the seat isnt that hard of a job, i would just take it out and pull the sending unit. its 8 bolts. good luck.

[mbgmike]

You can put a Rheostat and Ohm meter on it and verify if its the sender. Senders don't cost a whole lot. Generally run from $25.00 to $30.00.

[72hotrod]

I changed my sender with the seat full forward.

[da-burb]

to check the guage pull the tan wire at the tank and ground it out. Your gauge should go to full or over full tank when grounded. If it doesn't move it is the gauge or the wire.