Technical What can cause an upper radiator hose to go flat?

Drove my new to me 49 Ford with a 350 Buick V8 last night. Temperature didn’t show over 200 but opened the hood. The upper radiator hose was flat and it was sure ticking like it was scalding hot. My hose does not have a spring all the way through it so I will change that. could this be as simple as the thermostat sticking?

 

Head gasket can do that .

also if the temp sensor is nto in coolant it will nto read correctly. check the coolant in the actual radiator

 

The little flapper valve at the bottom of the radiator cap. It lets air(or coolant if you have a recovery bottle) in as the coolant cools down.

 

I asked the same question years back:

https://www.jalopyjournal.com/forum/threads/sbc-stuck-thermostat-or.1068486/#post-12126800

 

Yeah, I’m sure somebody had asked it before this search function doesn’t work the best for me. Thanks.

 

I tried several key words and my screen name. Still took awhile

 

First thing I plan to add is an overflow tank. I’ve got another vintage beer can, like I used on my model A. Then I will change the radiator cap and probably the upper hose also. Don’t think would hurt to change that thermostat at that time. Give it a good flush The car has not been driven much in past several years.

 

I changed both hoses and the thermostat.
Just realized I never replied for resolution.

 

You may need more than a flush, since you don't know the history of any related problems, and the fact that if it never had a "burp tank", I would guess that this issue has been going on for a long time. With no burp tank, every time it cools off, more air (aka oxygen) is drawn into the cooling system, causing significant rust inside your block. The upper hose collapsed because more than likely your radiator cap vacuum relief valve is completely plugged/stuck. Ugh..

Please don't use an old beer can for your burp tank.. Pick something you like and will fit from this list.
https://www.summitracing.com/search...awgr2Qv8ShMLR3i0BnKTG9A94L5yOGeob_7a6Ti39LghY

After installing the tank, start with draining the system then add
https://www.summitracing.com/parts/sum-tc001 .

Run it up to temperature, follow the directions on the bottle, be sure to have the heater going if there is a control valve on it. Flush out the cleaner two or three times, fill with 50%/50% DISTILLED water and antifreeze.

Oh, and get one of these. They come in different colors of your choice.
https://www.summitracing.com/parts/mrg-2471s

 

I like my vintage pul tab Schlitz can for an overflow tank and I will use it.

 

I just wish I could still find Schlitz beer. Tried it at spankys in Elgin Arkansas years ago while in a beer drinking competition with a real old war vet(I won ....he was impressed that a 21 year old out drank him on a new beer .....in fact he was the sole reason spankys kept Schlitz lol) and ever since I like to drink it now and again. But it seems to have disappeared the last couple years

 

I see. Pretty classy. The very first time your Schlitz burp tank overflows you will start the cycle all over again. Good luck. And you are welcome.

 

If you need more than a tall boy you could have bigger problems than a beer can tank.

 

New good quality 160-180 deg t-stat (with a small hole drilled in it), new 7 lb good quality radiator cap. You can use a puke can if you want just to catch it, it's not a surge tank. It's not a sealed system so be sure to use the proper style rad cap. If you want to make it a sealed system it's a different set of parts.

 

I use a can like that on my model and it works great. You run the hose to the very bottom of the can. It will puke it out and suck it back just fine. Use whatever you want on your car. Everybody that sees it on my car gets a kick out of it.

 

I think @squirrel did the same thing in his 9 second car as well.
Unsure of where the hoses went, but do recall a can as the overflow tank.

 

it looks bigger than 12 ounces maybe it’s a 16.

 

Yeah, I had a tall 16 oz can, so it was NHRA legal as a coolant catch can. Tube from the radiator goes down to the bottom of the can. pretty simple

 

And it’s that simple. And a Shlitz can!

 

I say, that’s why the NHRA chose 16 ounces.

 

Think of the 'can' as an expansion reservoir.
Hot coolant expands into the can and as the coolant system cools off it's drawn back in.
You want the hose to go to the bottom to return the fluid and not draw any air.

 

One thing to consider that everyone missed. What radiator do you have in the car? Stock Shoebox radiators with a stock style cap are not designed to be used with an expansion tank as cross flows are. The tank at the top of the radiator is the expansion tank and unless the car overheats or builds up pressure above and beyond the rating of the cap coolant should never go out of the tank or flow back into it with an orignal style cap of any pressure rating. That is why those 16 ounce beer cans are called puke cans when we use them at the drag strip to keep coolant off the driving surface if the radiator pukes.
If that upper hose is collapsing after you drive for a while and the car sits for a bit it is collapsing because there is a vacuum being created in the cooling system as it cools.
On the other hand if it collapses while driving there is a restriction aka stuck thermostat that the water pump is sucking against that gives enough resistance to create a vacuum that causes the hose to collapse. same as what happens on lower hoses quite often.