Thanks to all who provided hints.
I finally found the leak. My new method was to stand the tank on its end, access plate up, and fill the end with 1/4 - 1/2" soapy water. No leaks.
Make a circular dam around the tank filler cap with "Play-doh" and fill with 1/4" soapy water. No leaks.
Do the same around the sump. No leaks.
Turn the tank on its nose and make four "Play-doh" dams at each corner. Fill the entire back of the tank with 1/4" soapy water. No Leaks. Add more soapy water to the tank back to 1/2" deep. Leak!!!
That rivet hole was keyholed when I found it leaking and removed the rivet and covering Proseal.
The leak was at a Proseal peak and for some reason did not bubble, until I put it completely under water. Then Leak!!
I thought I filled it on the first repair attempt,, Oh well!!
Now at least I have a target.
I finally found the leak. My new method was to stand the tank on its end, access plate up, and fill the end with 1/4 - 1/2" soapy water. No leaks.
Make a circular dam around the tank filler cap with "Play-doh" and fill with 1/4" soapy water. No leaks.
Do the same around the sump. No leaks.
Turn the tank on its nose and make four "Play-doh" dams at each corner. Fill the entire back of the tank with 1/4" soapy water. No Leaks. Add more soapy water to the tank back to 1/2" deep. Leak!!!
That rivet hole was keyholed when I found it leaking and removed the rivet and covering Proseal.
The leak was at a Proseal peak and for some reason did not bubble, until I put it completely under water. Then Leak!!
I thought I filled it on the first repair attempt,, Oh well!!
Now at least I have a target.
