i have a 2005 bonneville se 3.8 both radiator hoses collapse,i have replaced both hoses and the hoses are still collapsed any ideas.
put a metal coil in like the old days to keep the hose open.
Is there a blockage in the over pressure line that runs to the over flow reservoir from the radiator? When your engine cools it creates a vac in your cooling system that draws in fluid from the reservoir. If this is clogged it would explain your collapsed hoses since they are the only other component of the system that is flexible. (Another possibility is your radiator cap is not functioning at the correct pressure limits.)
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