Why are my coolant pipes hard What Causes Hoses to Become Swollen

Why are my coolant pipes hard? What Causes Hoses to Become Swollen? If you notice that your coolant pipes are hard, it could indicate a few potential issues with your vehicle's cooling system.
Here are some possible reasons why your coolant pipes might be hard:
Overheating:
When the engine overheats, the coolant in the cooling system expands and creates pressure. This pressure can cause the coolant pipes to feel hard or firm to the touch. Overheating can occur due to various reasons