Here's two write-ups I made years ago, the first time I was a f/e on the 727. Now, of course, I've too much experience to make such poor entries:
1. Lav flush motor provides insufficient pressure to get the really big ones.
2. Left pack switch works 50% of the time. Only works correctly in the OFF position.
Both got big laughs from the mechanics, which proves that those guys do in fact have good senses of humor.