Welcome to LumberJocks.

Belt sanders work best with a slight crown in middle of each drum.
Does your Gil built have chambered drums?

Best Luck.

 

Also, you'll have to reach a minimum number of posts before pictures can be displayed, somewhere between 5-10 if I remember correctly.

 

Not sure what a Gil is, but most belt sanders have a tracking lever to shift the direction back and forth, but even with them if the belt is stretched, they don't do much.

Is the belt old? Might just need a new belt.

 

You may try removing the belt and flip it around then reinstall the belt in reverse direction. I've purchased off brand belts in the past that won't track, no matter what the adjustment. When I removed them and reinstalled them with the directional arrow facing the opposite direction, the belt tracked correctly. Food for thought.

 

Thank you all!. I will try reversing the new belt and check for crowning.