If you have an Accord with an F22 or F23
There have been some problems with the blocks cracking around the front mount bosses.
Two of our customer got free short blocks at over 75k when they started leaking oil and/or coolant. One a '97 the other a '95

Other reasons, severe overheating, impact damage, (either from inside or outside)
Improper installation of bolts in the block that bottom out or cross thread and are forced in.