97 lumina wont start

hi i am new to this forum. i have a question about my 97 chevy lumina 3.1. my ac compressor acted as if it dont wont to turn when the car is started. this only happens if the ac is off. but cutting the ac on the compressor spins freely withe belt. one day i drive to the store up the street and come back home for 30 min. and go start the car up. it will not turn over. i can here the starter engaging as well the light come on in the dash. i also checked the security light which is not flashing. i was told that the starter was the problem. purchased a starter and have installed by a mechanic. try to start the nothing happens still. now my mechanic tells me that oil pump is bad a locked the engine up. ok my car is full of clean oil which i change every 3000 mile. how could the it be the oil pump. i did not get a warning sign. could the ac compressor if it is locked up keep the car from turining over. i mean i trust my mechanic but sometimes he makes mistakes. my car has 240,00 miles on it. i mean it can be possible. but the car war running good and all off a sudden the engine is locked up. what is the world coming to. any help would be appreciated.

Somewhat confused by the description of your problem, does the engine crank but not start, can you turn the engine over by hand with a wrench on the crank bolt. If the ac compressor pulley bearing seized usually the belt would slip around it and the engine would crank over.

just take the serpentine belt off, and try to start it. The car should and will run without a belt for a few minutes.

sorry for the confusion. the engine will not turn over at all. i am almost certain that my mechanic tried to turn the crank shaft by hand. i am really bum out about this. the car ride good one minute and the next it wont turn over. how much is it for a rebuild or a good used engine.

As tblake suggested, did he take the serp belt off and try to start it then? I just had a Grand Am that wouldnt start like the starter or engine was locked up. I took the serp belt off and it fired right up. Went around the front of the engine and found the compressor pulley was seized.

I had the same problem. It was the A/C Compressor. Here is the post and of the problem. The starter was fried but it was the compressor that made it fry so good luck.http://www.automotiveforums.com/vbulletin/showthread.php?t=630907

thanks for the reply. i will try taking the belt off and see what happens.