And that's the only time. Not overheating at all. It's our 01 with 90,000 and had a fresh coolant flush a couple months ago. Kind of stuck. Found this thread but no real answer as my hoses are pretty new (2 months) with a fresh tstate.

https://landroverforums.com/forum/di...ng-woes-14772/

Any ideas? I just noticed it this morn while doing my weekly check on my wife's truck.

 

You can't compress water very much. So if the hose collapsed, what else do you think must be in there? I'm guessing air.

Bleed the system. If it doesn't stay bled, you have other issues.

 

I noticed a couple of my hoses were compressed after a recent cooling system flush. All hoses were brand new a few months ago when I did the head gaskets. After driving it a few times I bled the sytem and all seems fine now with nice round hoses! Which hose is collapsing?

 

Top hose with the bleed screw. I like you bleed the system and it seems better now. I intend to bleed the system again this weekend. Thanks.

 

Still have air in the system, it is creating a vacuum. Also check your reservoir cap for proper function, you may need to replace, double check for any leaks, you might be pulling air into the system.

 

So having a similiar problem. I happened to pop the hood the other day to check the oil, and noticed all the hoses were collapsed. Oil level was fine, coolant was fine, and not low. I noticed when I squeezed the hose, I heard a noise like a spring bouncing around, sounds like it's right around the thermostat. (not sure how else to describe it - if I dropped a spring on a table from a coule inches up, it would make a sound like that)
I started it up, came up to temp normally.... bled is a couple times, and got no air out of it (using the normal process of raising the coolant res 8 inches up, then cracking the bleed screw).

Any thoughts or ideas? seems to run fine, no overheating, no white smoke, etc, no lower coolant level....
thoughts?

J

 

Here's the spring. The bypass disk thermostat has a disk with holes. Normal running, coolant goes thru those holes (hot) and mixes inside chamber to make big part of thermostat open. If main part of stat is closed, and you move rpm above idle, water pump pressure would be too much for the heater core. So the bypass disk descends to allow more coolant to rush by and save the core. When main stat opens, it forces bypass disk back to sealed position. There is also a ball bearing or jiggle device in the flange of the stat to allow gas bubbles a way to pass, can make a slight rattle when shaken.

But you are either having a coolant loss, water does not compress, or a leak being replaced with air. May want to review pressure cap on reserve container, or consider doing a coolant pressure test with a unit rented/borrowed from parts store.

 

That makes sense about the spring, ball bearing making the noise.... oddly, when I have squeezed the hose historically, there never was that noise. I will do a coolant pressure test on it... (I have a close to brand new expansion tank cap...and on inspection, looks to be fine)

 

To follow up on this, after a good bit of looking around with no luck, I noticed there was a slight bit of coolant in the recessed middle of the bleeding screw. I had to use a flashlight to see it well. I concluded that there was a micro crack on the screw, and when it was at operating temp, some of that pressure escaped. As it cooled down, the crack closed, and thus, when it got back to stone cold, the hoses collapsed because of the slightly reduced volume. I had an old bleeder screw I took out from last time I replaced it. and put it in there.. Didn't work well as it wouldn't seat and promptly shot coolant pretty much everywhere. Went and replaced the entire upperhose, including the 'T' with bleeder and am good to go. I think I may have over tightened the bleeder screw at one point and cracked it.
I am getting a new thermostat to put in though as that rattling noise (mentioned above) was a new derivative, and it's a good time to just replace it.

 

consider the 82 C "soft spring" stat that will run the engine 6-10F cooler - from Justin at lucky8 and others.