A very large majority of us, if not all of us, have picked up a rusty engine or generator, only to be met with horrible fate. You cant drop it... Worry not, ill explain some ways that helped me with this issue.
1. Get killed by an enemy or by the elements. Yep, pretty harsh
2. Have the vanilla version of the game installed on a different device using the same account. Exit the hacked version, and load up the vanilla version. Once in the vanilla version, just drop the item, eat something(or save by some other means), and head back to the hacked version
3. (Not very useful if you can just follow the second method) But just delete the game and reinstall
4. Exiting out of the game. Sometimes works, sometimes fails.
5. THE MOST IMPORTANT ONE. DO. NOT. PICK. UP. HEAVY. ITEMS. UNTIL. THEIR. PURPOSE. IS. CLEAR. The only time you should pick up any of the heavy items in game, is if there is a clear place to put it. For example, at the motel, you'll notice that theres a gas tank outside. It has a very specific purpose, to be placed infant of the rubble inside the motel. The best way to know if a heavy object has a purpose, is to look around for blocked passages, non-functioning machines, or something else with the hand sign. Any of the aforementioned intractable components of the game should tell you what it is they require, whether its the northern watchtower which tells players it requires a generator, or if its the saw in the farm near the barn, which requires the barn(or farm) chest. So don't pick up heavy items until you're sure you know where its supposed to go
Thats about it, so yeah...