What will make upper radiator hose collapse on a 1998 4.6?
It is possible that your radiator cap is not allowing coolant to flow back into the system from the reservoir. I would install a new cap and check to make sure you have enough coolant in the system.
Perhaps trapped air in the system, try "burping" the coolant system first. Check your radiator cap is good and overflow hose is not restricted. A bad radiator cap might be sticking and not releasing the vacuum created by normal operation. Those should be replaced every two years anyhow. If the simple things don't fix the problem you'll have to look at things like restricted flow in the radiator/blockage and/or the water pump.
Ah, FoR, we meet again...
Agreed. Radiator cap. Cheap and simple fix
Good evening gentlemen
put a coiled radiator hose on as well
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