Ok, here's the story, 87 Fiero L4, took it out for a nice local ride, not much highway, mile from the house the left front caliper locked up. Replaced with a rebuilt, power bled the brakes, all fine.
Now the fun starts. Out of nowhere, no problem before, the radiator draincock starts leaking. Glued it in with Permatex Weld Seal, solved problem. Bled the system. Couple of days later big time leak from the back of the motor, water pump area. Hose seemed to have a little break, replaced it but the groove didn't penetrate the hose so wasn't the issue. With the system pressurized water pours out, much more then would come out of the weep hole. Turned an old radiator cap into 0 psi, filled everything, bubbles at the engine fill, no thermostat, all looked pretty good, minimal drips. Car didn't seem to overheat but at this point I was using plain water so i kept the radiator fan running. The weird thing is the car leaks more when not running. maybe as much as a gallon a night which is about what I was adding. Wondering if the system can be overfilled??. Leak seems to be coming from water pump area bur why more when not running?
I know all the ramifications of running the engine too cool (as is basically happening in my experiment) so lets skip that issue and just deal with the leak.
Take the belt off the water pump and wiggle the shaft. If that seal has failed it can dump a lot of water at times.
by the way,
"Old school rules."
I fall back on things like that 0 pressure cap many times on other cars to find a problem, as said though on a Fiero it may not work because of the height of the motor, now if you had put it on the thermostat housing it might have.
------------------ Technology is great when it works, and one big pain in the ass when it doesn't