drivers seat

my 94 ranger driver seat no longer engages when adjusting the distance from the steering wheel. the seat only locks when it is pushed all the way back. as if i let my sister use it she is much smaller than me and needs to be closer to the steering wheel the seat does not engage. i have checked the seat and cant quit seem to find out why it does not engage. is there something that i am not seeing. cant something be done do fix this.

There is nothing magical about how car seats move fore and aft (unless it is powered seat), If you look under the seat, all the operating mechanism (springs, slotted guides, pull lever) are pretty much exposed and easy to figure out.