Upper Radiator Hose Flatten
Thread Starter
Instructor
Joined: Jun 2006
Posts: 143
Likes: 1
From: Owasso, Okla
Upper Radiator Hose Flatten
On an 05 C6, noticed that when its full cold, the upper radiator hose colapses down flat. Started and running, inflates back up. No over heat or leak problems, just looks odd, and concerned of developing creases in the hose. anyone ever experienced that of know if it is a problem?
Burning Brakes
Joined: Jun 2007
Posts: 876
Likes: 141
From: Little Egypt, USA
Yep that is correct. Flat upper hose when cold is a symptom of a bad rad cap vaccum valve or in our case a coolant recovery tank cap.
When the cooling system cools the liquid contracts and air must be pulled in thru the cap to equalize the pressure or a vacuum forms which results in a flattened upper hose. Loosen the cap when the hose is flat and it should pop back out when the vacuum is released.
Don't worry however it will not cause any immediate damage to the system. If it's under warranty get a new cap from the dealer.
When the cooling system cools the liquid contracts and air must be pulled in thru the cap to equalize the pressure or a vacuum forms which results in a flattened upper hose. Loosen the cap when the hose is flat and it should pop back out when the vacuum is released.
Don't worry however it will not cause any immediate damage to the system. If it's under warranty get a new cap from the dealer.
