After spending weeks pushing a 21" around my yard in the South Carolina heat, trying hard to diagnose my engine troubles, and finally figuring out that my valve guides were shot (thanks to Restrorob and Fixdiss), I got a great deal on an 8 HP replacement B&S from a dealer in town who had some new-old engines on the shelf. I am dropping from 12 to 8 HP, but with a 28" deck it's OK. While I was at it, I also replaced the driven disk and painted the rear chassis and the back wheels. I took it for a test ride around the yard and it runs like new - cause it is. Check out the pics - by the time you read this, I should be out mowing. I didn't do it last night because I wanted the new paint to harden before I got grass all over it.