After the engine is cooled overnight, the top front radiator hose partially collapses.

I read some forums about the issue, so I removed and replaced the coolant recovery tank cap with a new one. The hose still partially collapses.

Does anyone else have that problem or a solution?

Photo attached.

Gary

 

The cooling system is pulling a vacuum when it cools and the coolant contracts. The problem is, what is letting a vacuum occur. Normally, as teh colant cools down, it contracts, creating a suction that pulls coolant from the recovery tank through the radiato cap suciton valve. The coolant recovery line may be plugged or kinked, the radiator hose may be old or weakened, the radiator cap suction valve may be inop.

 

I had the same problem...it was the thermastat sticking. I replaced it and all good. Another indicator is that my fans were coming on a lot after i turned the car off.

 

I'd also replace the hose while you do the thermostat and check the flow of fluid to the overflow tank in the fender.

 

Make sure it is installed correctly. Mine collapsed, cut off flow, and I could not figure out why until I realized the last person to install it, put it on wrong. I switched ends, and everything has been OK for the last 5k miles. go figure.

 

Does anyone know if the cap has a check valve in it that will release the vacuum?

 

The latest seems that the radiator hose going to the thermostat tower is weak. When the engine is hot, the hose appears to bulge. When the engine is cold, the hose partially collapses. The vacuum is supposed to suck the cold coolant from the recovery tank, through the overflow tank, back into that radiator hose.

 

If you think the hose is weak, then buy another. However, I suggest you first insure it is mounted correctly on your car. See my post above. gordo

 

they will weaken, even mine showed a bulge after only 7 years. Replace and sleep well.

 

Ditto H2Oboy's comment. Mine would collapse when cold, and bulge when hot (to the point of actually making contact with the fan shroud reforcing splines). Had it replaced last week....no more collapsing or bulging.

 

Got the weak lower radiator hose removed and replaced.

No more collapsing or bulging.

Thank you to everyone on this forum!

 

I think you will find the reason for the collapsed hoses is a malfunctioning reservoir cap. The reservoir cap serves two functions pressure and vacuum relief.

 

The hose replacement job is a good way to get familiar with your engine bay w/o getting into anything too complex, consider it a stepping stone to other, more complicated projects like coil-on-plug, or valve cover gasket changes, idler and tensioner pulley, etc.

How was that little short stubby hose that actually paired up to the thermo-tower? Was it soft or showing signs of bulging? it is also something that can blow pretty easily if left unchecked. Its hard to tell from the picture.