gas gauge help needed

on my 60corvair the gas gauge is pegged out to the very end past full,when the key is turned on if you look close enough you can see it move a bairly,i checked and ran a new ground wire and it didnt help,the sending unit is in the bottom of the tank so it seems like if the float was bad it would sink and read empty.Is there a way to test the gauge to see if its bad,i know with all the experienced hambers someone will know thanks,Howell.

 

if you short the sender wire to ground, it should read "empty" on the gage.

usually the sender gets a broken wire or connection or bad resistor in it, so it will read full all the time. sometimes the float sinks and it always reads empty.

 

if i short the sender wire to ground and it changes to empty does that indicate a bad sending unit or gauge

 

The sender would be bad. If you can pull out the sender check it with an ohm meter. When you move the float up and down the resistance on the meter should go up or down. If it stays the same its junk.

 

take it out, simple enough, and clean the wiper on it, the arm that moves with the float and rubs againts the coil built in the arm ,simple once you pull it up and see it, corrosion and years of gas shellac the connections, use a wire brush and little sharp knive and scrape the area on the arm and the coil, just a little cleaning needed have done it many times on alot of vehicles have owned many corvairs,simple float design


again read this forum http://www.virtualcorvairclub.com/forumdisplay.php?f=52

or corvair.org. way more help with everthing,keep you from having to do something more than once at the least

 

Your gauge is set to read a sender that is 0 - 30 ohms. Rule of thumb is to disconnect sender wire and turn key on, ground sender wire and the gauge should "sweep" from one side to the other. If it does then the gauge is good and so is the wire if you grounded it where it goes on the sender at the tank. If the gauge doesn't do a full "sweep" then it is bad. Check your sender when it is out of the tank with an ohmmeter. Move the float from bottom to top or vice versus, watch your meter to see if there are any "breaks" in the ohm range as you move it. If so then the sender is bad, if it doen't read when you move it then it is open= bad sender.