UPDATE:

Well, I didn't think it was serious. Turns out -- after a 1 hour pressure test -- that there was a pinhole prick in the upper hose. That's all.

Evidently, it was a very small hole and a fine mist, at hot temp it just vaporized. Therefore, no leakage. That hose was never even wet.

I think this thing may just run forever.

__________________
1994 C280, dark green metallic
105k miles

1991 190E 2.6, Black
191,500 miles
(sold to another forum member)

2003 Chevy Tahoe LT, Redfire Metallic
105k miles

1989 Mustang GT Cobra Convertible
43k miles