New upper radiator hose collapsed ?

[MassHoe04]

Update - this morning I checked and the upper hose was not collapsed. I unscrewed the cap and didn't hear any hissing. I think whatever hung up the suction check valve let go. Could have been 100% coolant that dried out in there while I was filling things back up. I don't know. I'm tempted to just order a new cap. Issues that go away by themselves often come back by themselves.

Could have been a chunk of rust from inside the block passing through... Maybe it got caught, then pressure from coolant flow could have broken it up, allowing it to pass like a kidney stone.

 

[Joseph Garcia]

Let us know in a few weeks, if your issue is still gone (hopefully).

 

[2006Tahoe2WD]

I replaced the overflow tank and cap. The new tank looks great.
Take a look. Old dirty 16 year old tank and the new OEM one.

 

[2006Tahoe2WD]

I was asked to report on the working of the original cap. It started working again - no collapsed hoses - but I replaced it anyway.

 

[Jerome Nelson]

I had this issue as well. I replaced the original cap with a new one from Advanced Auto Parts ($16) and it went away.
Later, I cleaned the old cap with a degreaser, soaked it in hot water, and replaced the new cap with the old one to test it out. The upper hose collapsed again while cooling. :/
Finally, I swapped the old one for the new one again - and haven't had any issues with it since.

 

[2006Tahoe2WD]

Yes, not worth messing around with trying to revive the old cap. Just get a new OEM cap and be done with it.