Answer :
Based on the scenario provided, where there is a coolant leak on the left side of the engine block and a history of overheating, we need to determine the most likely cause from the given options.
Radiator fins are leaking: While leaking radiator fins could cause coolant loss, they typically wouldn't specifically result in a leak on the left side of the engine block unless the radiator is positioned on the left and close to the engine block. However, this is less likely compared to other options that are directly connected to the engine block.
Expansion plug is leaking: Expansion plugs (also known as freeze plugs or core plugs) are part of the engine block. They are designed to protect the engine from freezing by popping out if the coolant inside freezes. If there's a leak specifically on the engine block's left side, a faulty or leaking expansion plug on that side could be the direct cause since they are positioned along the block itself.
Radiator is clogged: A clogged radiator could indeed cause overheating as it impairs the coolant's flow, preventing it from effectively dissipating heat. However, clogging doesn’t directly cause a leak on the engine block itself.
Crankshaft seal is leaking: This would lead to oil leakage rather than coolant. Since the crankshaft is located in the lower engine block, an issue here wouldn't cause a coolant leak on the block itself.
Thus, the most likely cause of a coolant leak specifically on the left side of the engine block, especially with a history of overheating, is option 2. Expansion plug is leaking.
