Yes this happened to me in the 70's it wore the rod down 3/8 of an inch and my car would not go up a hill. When I would turn around and get the car going down hill the gravity effect would take over and it would start and I did just like you are going to do put in a new one only to have it saw it down just like the other one in a month or so. you may want to save your time and money and just buy a electric pump or change the cam which I am sure you do not want to do. Good luck