I was mowing yesterday on my Ford 1500 and after a while of mowing I heard a squeal come from the engine and started to smell some rubber burning. I noticed the fan wasn't spinning and quickly shut it off. I was messing with it for a little while trying to free the fan but it wouldn't move. I did some research and found that the problem could be a seized water pump, since it is on the same pulley. Does anyone have any experience with this problem? How difficult is this to fix? Thanks.