I would start by replacing the radiator cap. A bad cap can stop the flow of coolant from the coolant reservoir back into the engine when the engine cools down. This will cause a vacuum and collapse the hoses.
The other possibility is the lower hose is starting to get weak. This compounded with a radiator cap that is not functioning correctly will cause the the hose to collapse when the engine cools off.
I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa
Answers & Comments
I would start by replacing the radiator cap. A bad cap can stop the flow of coolant from the coolant reservoir back into the engine when the engine cools down. This will cause a vacuum and collapse the hoses.
The other possibility is the lower hose is starting to get weak. This compounded with a radiator cap that is not functioning correctly will cause the the hose to collapse when the engine cools off.
I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa