[rjSupra]

my car seems to have a near identical problem as you described. It might be a little higher up in my engine. I have a full thread post here, and have not solved the problem yet. I am most likely replacing the upper 90 angle short hose just under the water housing / T Stat area. I hope it will solve my car hissing and blowing out 1 gallon of coolant in 10 minutes after overheating. I put in a brand new water pump (super super easy repair for anyone wondering - try this replacement on a damn Acura Integra that's never been changed or had it's timing belt replaced - the crank pulley bolt is impossible to remove - it's on at like 700 ft lbs from the factory).
and also a new T Stat, and both new gaskets, new alt belt and new A/C belt while I was at it hoping it would solve my leak which only leaks after I run the car 2000 rpms and above... It did not solve it, and I am scratching my head still... My lower hose is more or less as you described, a bit soft, foam corroded away near the clamp etc...