oil pumps

[gandolf52]

Hi all,
Just acquired a 1990 Grand AM with the 2.5 engine. The previous owner put a new engine in 9 mos. ago and since it has thrown 3 oil pumps. My question is does this engine have a history of oil pump problems? I haven't delved into the engine yet, so don't know anything first hand. I got the car for free so I figure I can put some labor into it and not be out much unless this is going to be an on going thing. I'm also not a newbie at mechanics just new to this particular car. Thanks for any insight anyone can give.
Eddy