Soak them in vinegar over night then a pressure washer will take off even really thick rust
A regular garden hose might work fine. I'll probably try a hose with just water this week on a couple traps that have been in pure vinegar. I doubt soap is necessary, given how strong vinegar is, although traprjohn's traps look amazing in that photo. Whether mine will accept speed dip after such a cleansing process is TBD i guess.
I wonder if a person has to let coyote traps air out for a while, before wax or dipping, for the vinegar smell to go away?