Radiator return hose collapsing

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ferrum
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Radiator return hose collapsing

Postby ferrum » Sun Apr 28, 2019 9:29 am

When my engine cools down, I find radiator return hose collapsed. What would cause this? Radiator cap is about year old. Is this going to cause issues? Coolant level looks good.
'76 Cherokee Chief

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derf
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Re: Radiator return hose collapsing

Postby derf » Sun Apr 28, 2019 9:39 am

Sounds like a defective or worn out hose.

I would replace it with a new hose. And while I was at it I'd just go ahead and replace all the hoses if they're old.

SJTD
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Re: Radiator return hose collapsing

Postby SJTD » Sun Apr 28, 2019 9:44 am

If the coolant return system isn't flowing back to the radiator somethings gotta collapse. Could be the cap.

Does the hose return to shape when you remove the cap?
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

ferrum
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Re: Radiator return hose collapsing

Postby ferrum » Sun Apr 28, 2019 9:53 am

SJTD wrote:If the coolant return system isn't flowing back to the radiator somethings gotta collapse. Could be the cap.

Does the hose return to shape when you remove the cap?


Yes, the hose return to shape when I open the radiator cap. It is strange.
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BCRAWLER
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Re: Radiator return hose collapsing

Postby BCRAWLER » Sun Apr 28, 2019 10:34 am

Just to verify, your not losing coolant. If so might be head gasket sucking fluid and causing vacum in system. If not leaking might be air in system. When hot air will expand but when cools down will take up less space and cause lower pressure and cause hose to collapse. My first call is to replace lower hose. If air in system this might clear it.
1980 Cherokee,360/727/208, propane powered,unknown lift,31' Adventuro's on Chevy rims,Warn winch
1980 J10,360/standard/208, stepside
1970 GMC 4X4 Pickup, 78 frame, 84 350, Turbo 350/205, patina galore
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SJTD
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Re: Radiator return hose collapsing

Postby SJTD » Sun Apr 28, 2019 10:57 am

The cap should relieve any vacuum in the system.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

BCRAWLER
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Re: Radiator return hose collapsing

Postby BCRAWLER » Sun Apr 28, 2019 12:51 pm

The cap releaves positive pressure but not sure on vacumm.
1980 Cherokee,360/727/208, propane powered,unknown lift,31' Adventuro's on Chevy rims,Warn winch
1980 J10,360/standard/208, stepside
1970 GMC 4X4 Pickup, 78 frame, 84 350, Turbo 350/205, patina galore
1986 Blazer K5, 350/205/465 trans
1990 Cherokee XJ, about to scrap for FSJ parts

SJTD
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Re: Radiator return hose collapsing

Postby SJTD » Sun Apr 28, 2019 4:41 pm

I am. It lets fluid flow into the overflow tank as the engine heats up and pull it back as it cools.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

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67GMC
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Re: Radiator return hose collapsing

Postby 67GMC » Sun Apr 28, 2019 4:53 pm

I would definitely look at the radiator cap but I had something slightly different happen to my Jeep. At idle, the lower rad hose was fine. When I revved it up, I saw the hose collapse. The water pump moving fluid faster was collapsing it. I got a new hose with an internal spring and haven't had this problem since.
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1984 Jeep Grand Wagoneer, 360 V8, Auto, SelecTrac
1987 Jeep Cherokee (XJ), 4.0L I6, Auto, Selectrac
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candymancan
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Re: Radiator return hose collapsing

Postby candymancan » Thu May 02, 2019 3:18 pm

You should have an internal spring on the return hose... all return hoses ive taken off have them. Including on my 90.

If you dont have one. Id get one
2013 SS camaro, cammed, and modded too much to say 500 RWHP/650 crank 40k
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