Right. If the engine was hydro-locked you wouldn't be able to turn it over. When the piston got to top dead center it wouldn't go any further. (Because the liquid in the combustion chamber will not compress.)

Stopping the engine after running it at idle (for any amount of time) then stopping it, will NOT result in a hydro locked engine, that only happens when you're priming the engine before it's running, so something else is going on.

We need more info to help, but I'm thinking that if it's a new(ish) ABC engine, then it's just tight (as it should be).
Dennis-