[PIC] Upper radiator hose collapsing???
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From: The artist formally known as NONO5.0 Mobile, Al
[PIC] Upper radiator hose collapsing???
Well, this is a new one. I haven't seen this before. When the car is cool, the upper radiator hose is collapsed like in the pic below 
At first, I thought it was a bad hose, but by the feel of it, it seems like the hose is ok. Naturally when the car is running, the hose is fine and like I said, feels ok. I'm going to replace it anyway, but is there something that could cause this to happen like some other problem other than a bad hose?
Thanks for any thoughts
At first, I thought it was a bad hose, but by the feel of it, it seems like the hose is ok. Naturally when the car is running, the hose is fine and like I said, feels ok. I'm going to replace it anyway, but is there something that could cause this to happen like some other problem other than a bad hose?
Thanks for any thoughts
Melting Slicks
Joined: May 2000
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From: Brentwood TN
Couple of things come to mind. If the coolant cap is removed when the coolant is hot, losing a tiny amount of coolant is normal since the system is under pressure of 15 psi or so. When the cap is replaced and the engine cools, the system experiences a vacuum causing the hose collapse you see. A lot of hose makers put a coil spring inside the hose to support the hose and generic (not molded to contour) hoses often have a molded spring molded within them.
Remove the cap when the coolant system is cold and replace it. The problem should go away.
Charlie
Remove the cap when the coolant system is cold and replace it. The problem should go away.
Charlie
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From: The artist formally known as NONO5.0 Mobile, Al
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Make sure your system is full too. Don't just go by the "FULL" mark on the tank. I have kept mine full up just below the "grid" you see when the cap is removed, for years. Works well, with no "burping" of coolant either. The upper hose can't collapse after cool-down if there's no air in it.
BTW, springs are used on pre-molded hoses on the suction side of the pump, i e lower hose. The upper hose is on the discharge or pressure side of the pump and does not need one.
HTH
BTW, springs are used on pre-molded hoses on the suction side of the pump, i e lower hose. The upper hose is on the discharge or pressure side of the pump and does not need one.
HTH
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You have a BAD CAP!! The cap should allow vacuum to pull through but NOT allow pressure out. Try a new cap. You can try to soak it in hot water/ detergent but to insure you solve the issue, a new cap is inexpensive.
BC
BC
Burning Brakes
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From: Coulmbia New Jersey
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From: Dear Karma, I have a list of people you missed.
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I experienced the partial collapsing upper hose too a couple years back. It was right after I had changed all hoses and flushed the cooling system, etc. I thought bad cap too. Changed it and the upper hose still was partially collapsing after cool-down though maybe not as much. Suspecting excess air in system, I began to fill the system with coolant to a higher level and over a period of a couple days the problem ceased.
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Melting Slicks
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From: pawleys island sc
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From: The artist formally known as NONO5.0 Mobile, Al
Thanks alot for the info everyone!!! 
I took the cap off and heard a good bit of air released and naturally, the hose went back to normal. I'll also look for a new cap monday!
I took the cap off and heard a good bit of air released and naturally, the hose went back to normal. I'll also look for a new cap monday!
Team Owner
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
BTW, don't be surprised if the replacement cap (GM) is an 18lb. As far as I can tell that is now the standard pressure rating.
Le Mans Master
Joined: May 2005
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From: Fort Lauderdale, Florida
I had the exact same thing happen to me recently after changing a thermostat. Just do the procedure for bleeding air from the system and refill and you should fine. I didn't need a cap and you probably don't either, unless you can determine that you lost coolant and hadn't been opening the system previously.
Safety Car
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From: San Rafael CA
I had the exact same thing happen to me recently after changing a thermostat. Just do the procedure for bleeding air from the system and refill and you should fine. I didn't need a cap and you probably don't either, unless you can determine that you lost coolant and hadn't been opening the system previously.
