Gas Gauge help

I have a stock 66 gas gauge in my truck and it reads all the way full when the tanks is full but only sweeps to half. When it finally gets to half the tank is empty. any advice on what to check for?

 

Inspect the float resister for wear.

 

And while you have it out, check the contact points on the resister wire on the sender. They get coroded and a little cleaning helps.

 

is it possible that the float has a hole in it and takes gas in? I pulled my gas tank on Friday and found that the float was full of gas. (seeing as how the truck has not been driven in 5+ years i have no idea what the guage was registering).

 

There was a recent tread recommending the ISSPRO sending units which is a canister with no float arm. You order by length and resistance. I recently received one but will install this week. Seems like an improvement to the float arm type, but expensive. Check their web site. The FOGGER

 

Take a fine point marker and draw a letter 'E" at the 1/2 point. Problem solved!

 

Has to be a fine point?

 

Thanks for all the input will get it out this weedend and have a look see