engine sputter after rinsing

[GREASEMONKEY72]

i used to always be able to rinse my engine off with out any problems till the last 3 times ive done it

the first of the 3 it wouldnt start unless i held the choke plate open and then it would sputter everytime you touched the pedal

then these last 2 times it starts fine but will sputter if you touch the pedal and it even died out while i was moving it around on the lawn the time before last and even backfired through the carb

i pulled the carb off and made sure the screws were tight and made sure its tight to the intake, checked and made sure the intake bolts were all tight and the manifold bolts aswell

any ideas???