They make a rebuild kit for those. Easy to do just watch out for the little springs. Pretty sure this is it. Stay away from the cheap chinese $20 ones they are nothing but trouble. A factory pump is $170 the rebuild kit is $16
0393088
Push the small lever up just until you feel friction. Push key in while starting. Be prepared to push the small lever down if it starts and takes off. May be some trial and error to find the right setting. If the small lever is up you should not be able to shift.