Scanner head Doesn't reset or scan from edge of glass OfficeJet 8600

My officejet 8600 scanner head will scan through the document feeder just fine, but when placing anything on the glass the scanner starts out about 3 inches from the right and cuts the paper off, whenever I try to preview a scan it will go all the way to the left and jam up against the end and give the "unable to scan, copy, fax" error and needs to be powered off again to reset it. but even then, it starts out at the 3 inch spot
I have taken it apart and manually set it to the right edge and it actually works for a few scans but then starts again from 3 inches.

does anyone know of anything else I can do? it's just a month out of warranty and it's not worth it to me to send it in.