Yesterday, in prep for losing power at the marina at noon today, I fired up the genny to check everything. For the first time in our nearly 7 year history, the NL 16KW genny didn't instantly start/run. It started, ran a few seconds and died. Started again, ran a few seconds and died. Started again, ran perfectly. No, this thread is not about figuring out the issue but it got me to thinking about something else.

Actually this thread is to ask the question, "Did the "need" for having zincs in engines undergo a change sometime in the past?" The reason I ask is that my DDs have fittings for 3 zincs in each engine - one on the RW pump housing and two in the HE (though I only use one - on the outlet side of the HE). The NL genny has no fittings for zincs at all nor any mention of them in the owners or service manual

Near as I can tell, the mains/genny engines are made of the same materials as are the HE cores, etc. So it seems obvious to me that at some point there was data or whatever available to engineers to lead them to believe that zincs were not needed.

A few months ago I pulled the genny HE for the first time since we have owned the boat. I cleaned it but frankly, there were no deposits in the HE at all. So, what was the "data" that made NL realize that zincs weren't necessary? Do currently-made marine diesels have zincs?