The only time leaving a bushing in a block during cleaning would be problematic is if the oldtime caustic boil-out tank is used. The "oakite" solution we used 50 years ago would eat diecast seal holders and bronze bushings. Most machine shops quit using caustic hot tank cleaners many years ago due to harassment from the tree huggers.

A regular rotary pressure washer that uses hot water and strong detergent shouldn't hurt a bronze bushing. You should inspect it for wear, however.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!