Upper and lower radiator hose replacement, water leak from rear engine now Options

[layingpipeinda91...]

Hello Folks, I was helping a friend with his 1996 celica gt 2.2 automatic, convertible, the upper radiator hose sprung a leak, while he was driving home from work as a corrections officer, his drive is approx 70 miles. He tied a rubber glove about the hose and put some water in the over flow container. He made the drive home and parked it. I came two days later with the upper and lower hose and had them replaced in less than 30 minutes. we filled the radiator with 60/40 mix and turned her over waiting for thermostat to open and began adding water through the reserve, each time the radiator fans came on the reserve would empty. I then noticed a leak as water was dripping down from under the rear of the engine compartment. I checked the radiator, its fine, the new hoses are fine, the heater core hoses are good, I tried to inspect the water pump and cannot see any indication of water leak and it sounds good when running, the thermostat housing in good and dry, so I am thinking that maybe a core plug has gone bye bye? Any one with suggestion or pictures of where and how many would be awesome. I did let the car cool down over several hours and opened the radiator cap, the water level was only a little low, I squeezed the lower hose and water presented at the cap opening, but the upper hose feels like there is nothing inside it. I used garden hose to trickle water into radiator and water in was matched by water out from where ever this leak is. Again any help would be most awesome. James.