Help : Toilet problem!!

Old toilet bowl was leaking down to a certain level gradually everytime it was flushed. Sounded like a crack in the bowl.

So got a new toilet, installed toilet to the floor & mounted the tank to the bowl, as a test before hooking the water line up took a bucket of water & poured this into the bowl. This acted similar to flushing the toilet, most of the water drained out of bowl. I actually expected the water to stay in the bowl.

Do I have a different problem?

A toilet bowl is sort of like a teakettle...it should hold water until the level exceeds the outlet of the spout (in a toilet, it's called the weir). If you pour the water fast, it DOES act like a flush, and the level will be lower. When you flush, the fill valve directs water not only to the tank, but also into the bowl to refill it. If you pour the water slowly, it won't active the siphon, and it will slowly just go over the weir and only fill to the 'normal' full point. IOW, what you saw is probably normal, unless it slowly drains over time by itself.

If you pour a bucket of water into a bowl, it will siphon itself dry.
What happens if you flush and allow the toilet to refill?

The reason I ask, is that while the tank is refilling, it should also refill the bowl.