upper radiator hose collapses when cold (1 Viewer)

[mikgrail3]

92 with 3FE and 225k miles - new upper and lower radiator hoses, new water pump, radiator replaced two years ago.

I noticed this morning that the upper radiator hose was collapsed (sucked in) while I was fixing a cracked battery post clamp. What would cause this? We spent about 6 hours in the desert yesterday in 105+ temps with no cooling issues at all. Would this indicate that my cap is starting to fail or is it normal?

Thanks

 

[Michael Hanson]

Cheap hose or worn out , maybe ,get one from Toyota or one with the coiled wire in it. 2 cents MIke

 

[mikgrail3]

It is a Toyota hose. I replaced it back in March, it's basically brand new. Sticker is still on it I believe.

 

[voorland80]

Did you change the hoses just prior to your trip?
After changing the radiator hoses, did you allow for any trapped air to escape?
It sounds like cavitation to me. I would try evacuating the cooling system of any trapped air by running it until the thermostat opens and it overflows at the radiator cap (with cap off). Cap after it releases all trapped air bubbles and check overflow bottle so that coolant is at proper level.

 

[voorland80]

Here is a link with excellent explanation of cavitation:
What is Cavitation?
Thanks to wisegeek.com

 

[mikgrail3]

The dealership did the water pump for me and I had them do the hoses at that time as well. So back in March. The hose does feel real squishy. I wonder if I got a bum hose.

 

[Michael Hanson]

If its low on fluid it will suck back up the overflow fluid as it trys to refill the radiator. Keep filling up the overflow each night until it quits getting sucked up. Also check ALL water hoses all the way back to the rear heater. MIke

 

[Marc311]

Bad cap? As Michael Hanson stated, the heating system expands and contracts. A faulty cap could be allowing fluid or air to escape, but not allow it to return. I did a quick google search to verify my theory, and it looks like a bad cap can do this.

Caps are cheap and should be replaced regularly anyway - so if you haven't replaced it in awhile, can't hurt.

 

[mikgrail3]

Ok, I just looked under the cap and the coolant was a little low in the radiator itself. So I filled the radiator and then ran the truck without the cap on. At first I saw small pin head and tip sized bubbles. One or two at a time. After about 10 minutes I did get a burp. Large enough to drop the coolant from the very top of the fill hole to just below the overflow hole to the overflow tank. Maybe that was my issue like stated, cavitation and air in the lines. Thanks for the help and I'll keep an eye on it in the morning when it's cold again. I appreciate all the quick responses!

 

[mikgrail3]

Oh and I'll get a new cap just to eliminate that as a suspect as well. Cheap insurance I guess.

 

[Gumby]

Replace the cap.


If you saw it collapsed after it had cooled off and while it was not running, it's not pulling coolant back from the overflow.

Normal hose collapse happens on the suction side while the vehicle is running. It sounds like yours was not and the 3FE is a normal flow cooling system. The bottom hose is under suction not the top like a 1FZ.

 

[cruiser tech]

replace the cap.