Starter can not turn engine (new starter, batt, and wires)
 

Okay I have a 1996 Chevrolet Corsica, with a 2.2L L4. Here's the deal, it ran and drove fine until last night when I was servicing injector seals. I noticed one of the injectors was leaking fuel outside the manifold so i bought new o-ring seals, replaced them, and put it all back together. In the meantime the battery died because the dome light was on for a good hour or two. I didn't think it should have died so soon and after trying to charge and then checking the battery verified it to be a bad battery. Replaced the battery, and still would not start. Starter engaged and sounded like it was "trying" to turn the motor but couldn't. Thought I had a defective battery, so exchanged it, and also replaced the battery cables, thoroughly cleaned starter terminals and ground point before attaching them. Same problem with new battery and cables. So then I thought it must be the starter. Bought and installed a new starter, checked all connections several times, and STILL the SAME problem. When I turn the key the starter just makes a clunk like its hitting the flywheel and meshing with the teeth but not turning it. then every few attempts would result in the engine turning just a little bit, but not much, before locking up. It sounds like the starter is encountering some kind of resistance. I seriously doubt its anything electrical or to do with the starter. I removed the accessory belt to ensure no seized accessories, to no avail. I don't know what would cause this or how the engine could lock up.

Please help... its my only car and i cant get to work or school.. its urgent