I think your problem is there shouldn't be any adhesive on there, its an oring seal be sure to smear some grease on the oring before you put the cone back on. i haven't herd of the grease eating the oring if your worried about it use a silicone ar synthetic grease on the oring. but for what your doing it is not necessary to pull the cone in the first place, however it wont hurt to inspect the grease and bearings. there should be not water in there and clean grease.
or you could just let it be......