i have grooves in my block from a crappy bearing in a pump once...make sure to flush your cooling system. if you have a new water pump, most likely its not the cause of your noise. the block on your motor won't bend, only crack or shatter. there are plenty of other things that could make that noise. my money would be on the idler pulley or air conditioning compressor, but it could be the power steering pump as well. listen around your belt system see if you can track it down
