Bruce,
1. The noise is tapping and comes from the muffler.
2. I have read the writing on the blade package and installled the blades, washers, nut and bolts as indicated. No problems here as I have been doing this many years.
3. As I had not used the mower for about six months, the blade plate was not scarthced or shiny. The blades did move back when pushed.
4.The starting is normal without any rope pull back.
Although this mower is 17 years old, it is well maintained and has full power.
I have recently changed the blade plate from two blade eliptical one to four blade circular one. Mower works fine except the noise.
Hope I have given you all the answers you need.
