I recently aquired an old 1972 simplicity 728 from a friend, he said it would not start one day and it was too old to look at. I got it home and found the pto belt broken, I have no idea how the pto system works on this thing but I see 2 horizontal pulleys in front attached to the pto engagement lever and one pulley all the way in the middle of the deck. What am I looking at and can I still get replacement belts for this?? On the engine side, the welsh plug is missing from the carb and it leaks so I suspect a carb rebuild is going to happen. The motor just doesn't seem to turn over fast enough to start. Even with my jumper pack it, the starter can't pull past the compression stroke. It has one of those big starters ive never seen before. Can someone explain what I should try? It has a Briggs and stratton 8hp engine I believe.