Changed out leaking heater hose....drain and refill ...bled air...thermo good...no idle issues ...So I'm off for a some laps around the block....and all of a sudden gage is pinned hot ..we smokin...pull over...lift hood.. upper hose broke off with ...part of the neck in tube with clamp ....pull the pieces out....looked like baked cardboard....very brittle....crumbles in my hand.."Aim me in right direction"...

 

it's likely at the very least your head is warped

compression test to confirm

 

My head yes...I agree... new radiator/thermostat on the way...after install.. I will check compression..have you..heard of or had that happen to you...what do you think caused it ...

 

It's possible the thermostat stuck closed and that is the cause, then the head warped and hot exhaust gases got into the cooling system and had fun with the cooling system components.