If the above two posts are to be taken as correct, then it points to something wrong with the installation of the starter, and/or a (partly) seized engine. Using the principles of checking what's easiest first, I'd suggest next step is to bar over the engine. (If you can't do this, or you don't know what a "normal" engine should feel like for resistance when its done, there is little value in yourself doing so).
The other possibility - incorrect starter installation - has so many variables that its not worth going into them just yet (without sight of the engine it would be a guessing game).