Today has been a sleepy day, but it started with honest work.
Yesterday I bought two quarts of SAE 30 oil for our two lawnmowers. The mower we bought hasn't had its oil changed since last year and who knows about the other one.
The oil reservoir has a plug on the top side of the engine (where you add the oil), but there also appeared to be a drain at the bottom. I didn't have a tool to unfasten the lower screw, so I drained from the top.
I lifted the body of the mower--I'm betting He-Man would change his oil this way too--in such a way that the spark plug remained the highest. I had a bucket to catch the draining oil. It was dark black and runny like water so I'm glad I did it.
After I emptied both mowers I put about 20oz (.6L) of the SAE 30 into the casing using the fill/drain hole.
I'd have a more interesting post, but, again, it's been a sleepy day after I accomplished that small feat.