I'm looking for some help. I have a very clean, second owner 94 coupe. When we bought it 3 and half years ago, it dumped a quart of anti-freeze at a car show. No one could find where it came from. The next day I tightened all the clamps and checked the hoses. I had to order a short 90 deg hose that came off a tee in the top hose that didn't look great. No more leak! We put 5k on it without a leak.
Last October I backed in next to my son's C6 in front of a restaurant and it dumped another quart. There was one drop on the lower hose. Drove home 15 miles, no problem. Next day drove 25 miles, put in garage, for 8 hrs, it was dry. Went to leave in the morning but another puddle!
This year I doubled the clamps. We drove it Friday nite, went to a
car show Saturday nite and put 40 miles on Sunday. Garage was dry Sunday nite. Monday morning, another puddle.
I tried pressure testing and adding clamps. The water pump is good. Any ideas? Other than replacing all the hoses and the rad, not sure where to look. I've been a mechanic for 40 yr's and never saw a leak that happens 8-12 hrs after driving and not while running. Car has 78k on the clock.