Collapsing upper radiator hose

Cubey

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I went to do something under the hood and found this:

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Sorry about the very poor framing, it's one handed cell phone video. You can hear and half see the hose pop back to normal when I fully pulled out the radiator cap.

It has a new radiator cap. At first I did the release lever to let off the pressure (vacuum) but nothing happened. It has a 13psi radiator cap and it's listed as fitting an 85 6.9 so it should be the right thing. Did I get a dud?

It's a brand new hose too.
 

Chief

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I put a safety lever one on my dodge and it worked fine. Were you able to get it fixed? I probably need to do the same to my 7.3 since it appears to have a non Motorcraft one.
 

Shadetreemechanic

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Pulling a slight vacuum as the engine cools is normal. That is how the coolant blown in the overflow tank when the engine gets hot gets sucked back into the radiator.
 

Cubey

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Pulling a slight vacuum as the engine cools is normal. That is how the coolant blown in the overflow tank when the engine gets hot gets sucked back into the radiator.

That seemed more than slight to me. It was like it created a vacuum then closed itself off, as if it pushes coolant out when warm and the coolant expands, but fails to pull it back in, causing a vacuum when the coolant cools back off. That would be under the control of the radiator cap. I think I might try the $6 basic Murray radiator cap. It beats the risk of overheating from a collapsed hose.
 

Cubey

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Top hose is pressurized by water pump when running. Bottom hose collapse causes overheating. That is why it has the wire spring inside it.

It has a new bottom hose too. The probably original hose sprung a leak recently. I caught it immediately as I was doing other under hood work. The spring inside still looked perfect so it went into the new hose.

After doing under hood work yesterday which involved starting it and stopping it several times, it was extremely collapsed this morning when I went to look.

It's a bit low on coolant in the radiator from the hose leak, the draining of it for replacement of all the hoses and not putting back in the worst of the coolant. I bet that's the problem, it's sucking in air, not coolant.

It was still below freezing at night until recently, so I couldn't do a cleaning flush at the time. I also just noticed that it has emptied the overflow bottle that I filled a month ago, so it seems to be functioning properly. At one time, the radiator was full too, but it probably has since purged more air in the system.

I'm currently house/pet sitting for a relative while they are out of town for a couple weeks, and I have use of their car and driveway, so I'm not driving it anymore until I do a bunch of work, including a full cooling system flush and refill with fresh Zerex G05 I already bought last month.

It seems to be remaining above freezing now, so I plan to drain it again and dump in two bottles of Blue Devil radiator cleaner that I got recently on sale. It calls for four bottles for the capacity of an IDI, but I don't want it to be too harsh, plus AutoZone only had two bottles left when the sale was on. Two bottles should still help. I will take it out for some driving to help circulate it, not just fill and idle.

I just need to decide if I want to spend $1/gallon for distilled flush water, or just buy 5 gallons of filtered water for $1 at an automated ice/water stand. (1/5 the cost). I really want to do a thorough flush until it's coming out clear.

Filtered should be way better than straight city water, which has a LOT of scale(?) here. My 1950s aluminum coffee percolator pot that I use daily to boil water gets a ton of it from the city water here. So much that you can make a small pile of it after just a few weeks of use without cleaning it. It's like a very fine sandy substance.

If there was space for a coolant filter, I'd probably add one, but seriously... in a van chassis, there's no room. Especially with a turbo kit! The water separator was put under the driver's seat with a hand/pull cable you accessed under a plastic hatch cover inside. I'd have to run 20 extra feet (10 in/out) of heater hoses way underneath someplace to mount a filter base. Maybe someday, but not right now.
 

YJMike92

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A faulty Radiator cap or a restriction in the tube that leads to the recovery bottle. It is not unusual to see an upper hose sucked into a vacuum after engine cool down if you are unable to pull the coolant out of the recovery bottle.
 

frankenwrench

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Just had same issue. Turns out I put in a powerstroke t stat and it was already sticking. Replaced with motorcraft and it solved that issue. And I specifically asked for a moter craft the first time for an 85 idi and the dummies still couldn't find one for a powerstroke so they gave me one for a 95. Wen I went back after pulling the wrong one out they argued with me for about 5 min before I pulled a part number and had them pull that. Tried to argue about what I had under my own hood like they knew better than I did and "idi's" were a figment of my imagination.
 

Cubey

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Just had same issue. Turns out I put in a powerstroke t stat and it was already sticking. Replaced with motorcraft and it solved that issue. And I specifically asked for a moter craft the first time for an 85 idi and the dummies still couldn't find one for a powerstroke so they gave me one for a 95. Wen I went back after pulling the wrong one out they argued with me for about 5 min before I pulled a part number and had them pull that. Tried to argue about what I had under my own hood like they knew better than I did and "idi's" were a figment of my imagination.

There are some real dummies working at some auto parts stores. Someone at an O'Reilly once told me that metric brake lines don't exist because they didn't have any. The Napa across town had the "non-existent" brake lines in stock, go figure.
 

IDIBRONCO

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I will take it out for some driving to help circulate it, not just fill and idle.
In my opinion, this is the best way to do a flush. The water pump will be turning faster, creating more flow in the engine, and should pick up more heavy deposits than just idling. It also gives you more to look at than just your radiator cap.
 

frankenwrench

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There are some real dummies working at some auto parts stores. Someone at an O'Reilly once told me that metric brake lines don't exist because they didn't have any. The Napa across town had the "non-existent" brake lines in stock, go figure.
Lol had the same non existent wristpin issue at O'Reily with the manager, my wife's boss, and told him just what an idiot he is and why tf is he the manager of a parts store. I also went to Napa and they found them and ordered them and just to be an a-hole cause he was trying to insult my wife's intelligence as well she didn't come straight home. Appearantly she made a bet with him 300 bucks or her job and the truck so she had to bring them in to show him and collect. She is now district merchandiser. Lol. I love that spiteful woman
 

snicklas

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The above is why I go to my local auto zone and talk to Tim. He’s the grey haired guy with the brick setting in the parking lot........
 

frankenwrench

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Our local AutoZones are just as worthless and dumb. We used to have 1 guy a few towns over at an AutoZone named Brad that was verry intelligent and helpful but he moved on to better things a while back. Used to drive 30 miles out the way to avoid the ignorance and speak to him. And he was a Dodge guy!
 
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