What Are the Causes of Engine Block Cracking?

[Richard]

There are many reasons that can cause engine block cracking, such as adding water instead of antifreeze to the radiator. When the outside temperature is too low, the water inside the engine block freezes, causing the block to crack. Engine water shortage, overheating, and then adding too much cold water directly or splashing cold water onto the engine can cause the engine block to crack due to thermal shock. Severe impacts can also lead to cracks in the engine block. Engine Connecting Rod Fracture: Water entering the engine cylinders can cause the connecting rods to break. When a vehicle drives through flooded roads, water can be sucked into the cylinders. The water initially entering the cylinders quickly turns into steam due to the high temperature of the block, making it impossible for the cylinder to form a combustible mixture. As more water enters, it accumulates on top of the piston, reducing the effective volume of the combustion chamber and increasing compression resistance, which in turn increases the pressure transmitted from the piston to the connecting rod. When the water volume reaches a certain level, the compression stroke essentially becomes compression of water, drastically increasing the pressure on the connecting rod, causing it to bend, deform, and eventually break, potentially even rupturing the engine block. Repair Methods: To repair a cracked engine block, use coarse sandpaper to remove rust around the crack. When sanded to a certain extent, the terminal point of the crack can be identified. Then, directly weld a repair plate, but be cautious of warping at the welded area. If warping occurs, it must be hammered while hot to prevent residual slag. After repair, place an asbestos gasket between the repair plate and the block, and apply a layer of lubricating oil on both sides.