Re: Engine temp? 230?
Those I/C flatheads are some of the most durable stuff B&S ever built. I saw them come in with the cooling system packed full of debris, and overheated to the point where the head gasket failed. The complaint? "Hard to start, no power"
Run it out of oil & the rod will fail. Usually that is just a rod replacement. Over speed was the only time I ever saw holes in blocks.
Again, the biggest factor for longevity is oil. Enough of it, the right grade, and frequent oil changes.
For equipment that gets rolled & shaken while running you need to fill the sump to the top of the fill plug threads on the engines with the low mounted fill, or 1/4" ABOVE full on engines with a dipstick mounted at tank level.
All of those 93432 series engines were designed when regular motor oil had 1800 ppm (or more) of zinc. Emission controls on cars has led to the removal of zinc from motor oils. Even oils for diesels have reduced zinc levels today.
You can find oils with higher zinc levels from several specialty oil vendors (Lucas, Schaeffer, Brad Penn, etc) or use an additive. Lucas sells an additive called TB Zinc Plus that does great job. An ounce per quart brings the zinc level up.
If you doubt the need for zinc in splash oil engines, look at Jr Dragster. They tend to run as much as 6,000 ppm of zinc in their oil.
I always told customers to do 50 hour oil changes. For a guy with a truck mounted sprayer & your engine that meant an oil change every two weeks. There was some resistance to that, but the people that listened - all I ever sold them were spark plugs and air filters.
FYI, running without an air filer will destroy that engine in a few weeks...