Re: 70 hp Evinrude stalling
1974 model.
What is this "external annode" you found on the transom? Where does the wire lead to, and where on the motor did you connect it?
What exactly do you mean when you say "stall"? The engine shuts down? Boggs down?
Sounds like it's running on 2 cylinders when that happens.
Unless by "cleaned the carbs" you mean "disassembled, soaked overnight in carb cleaner and reassembled with new carb kits" followed by a link & sync, then your carb work is incomplete.
But 3 things you need to do first, before any other maintenance:
1. Buy a repair manual. I highly recommend the factory shop manual.
2. Compression test.
3. Spark test. Use an inline tester ($5 at autozone), set the gap at 7/16", clip it to the engine block, attach the plug leads (one at a time) and look for a strong blue spark while cranking.
report your results.
Also inspect the fuel tank for water & debris, make sure the fuel is fresh, the tank vent is open and clear, and the spark plugs are champion QL77JC4 in good condition, gapped at .030.