Snapper makes a few self-propelled mowers equipped with the Kawasaki FJ-180V engine. AFAIK, this engine is the only current walk behind mower engine with full pressure lubrication, which is essential for mowing on a steep hill (i.e., one with a slope greater than 20 degrees) in order to prevent oil starvation.

The Kawasaki-equipped Snappers are expensive (around $700), but they're well built and will last a long time with proper maintenance.

Hope this helps.

Make sure the muffler and ports are clean on the Lawnboy. It should be able to deal with that hill. And being a 20cycle not having to worry about starving it of oil.

The Snapper sounds nice but its also $$. I personally like the Hondas. I consider the Kawi the best engine and the Honda second best. I have the Honda HRR216K5VXA and its great. $500 at the box stores. Now there are inclines and there are inclines. My rule is that if you can walk on it , you cam mow it. If its too steep to even walk on it, I would not put a machine on it either.