Great Discussion Guys, There isn't enough oil in most of today's engines to get past the rings and cause Hydro-Static lock. That would certainly be a consideration when the engineers designed a 'Service Position' to begin with. Lawn tractors are a different story (horizontal vs vertical cranks, plus, did he lay that tractor on it's hood?). The biggest issue with oil leaks I have, is when I pull 40 snow blowers in at night, and put them in "Service Position', some of the machines will leak a small amount of oil from the dipstick tube/fill tube. I use old disposable rubber gloves.... take the Dipstick out, push the stick through the old glove, then insert stick in tube and tighten down. Fuel usually isn't a problem, as most units are brought in empty or I have already drained the fuel and put a small amount back in. But the old gloves would work for that application also. GLuck, Jay