When I change the zinc, I put Teflon tape on the pipe thread, reasoning that the metal will cut through and allow current to pass.
It seems to work, in the sense that the zinc corrodes away over several months.
However, I can measure a few ohms resistance between the brass plug head and the engine block. Is this OK?
Should I install the plug dry, or with grease only?
BTW, we find it easy to change the plug without draining seawater from the engine. Just close the intake sea**** and run the galley seawater pump to create a vacuum. No leaks
As long as you have good continuity between the plug and the housing, you should be fine.
I personally prefer to fit them dry but have used a single wrap of PTFE tape when I had an issue with a water leak.
Stanley
