Hello !
As it is on acceleration, IMHO you may have destroyed (i.e. transformed into black goo) the rubber washer that serve the exact purpose of preventing the clonk.
The parts are cheap, but you need some time to replace them, first to dismantle the fork, then to clean the mess then to reassemble and put new oil in.
It is item # 24 on the fiche. They had 3 versions : original in black rubber (making the goo) then in white translucent sort of plastic which explode in small cube of hard and brittle plastic a PITA to clean, then in orange synthetic material which will fail in
?? We don't know yet.
Anyway, you're good to open and check. Wear gloves.
