WHAT ZINCS??

[Bluewater]

Purchased Sunshine at the end of November, 2019, and was assured that zincs had been changed in the previous 10 hours - and the boat was kept in a fresh water canal. I’ve put 85 hours on the Yanmar since then but didn’t feel that changing the zincs was top priority during the last six months.
But changed them yesterday along with the fuel filters.
Ha!! See below........ How wrong could I be?!

How frequently do you (Yanmar 6LP) check/change your engine zincs?

ED84B619-CDD2-4055-9A7E-F6E2F66F32BD.jpeg

[RobS]

She was slipped in freshwater and anodes were changed last during her freshwater life. Do you know if the prior owner was using magnesium anodes? Mg would only last 25% to 30% as long as Zn would once the boat was moved to saltwater.

Also, are you in a marina? If yes, ask your boat neighbors how their Zn life is ….. , remember you are connected to your neighboring boats via the shorepower ground (unless a galvanic isolator is installed) so if something is going "astray" (pun intended) for one boat it becomes the problem of many...

[Bluewater]

Thanks, Rob. Previous owner was evidently careful about maintenance and the records show zinc zincs (assuming that they are correct). Boat slipped in fresh water but used in salt - Tampa Bay Area. So a fresh water flush between the lock and the house.
My immediate neighbors are up on lifts, but there are plenty of boats in the vicinity with shore power connected as with the majority of marinas.
I had galvanic isolators on my larger steel sailboats - but not on Sunshine.
Still interested in how frequently other 6LP owners check/replace their zincs??

[MadMoney]

Hi David -

I'm out here in Seattle and my boat spends the winter in fresh water and 5 months of the summer in the salt. My mechanic checks them twice a year during my service routine and changes them accordingly. Zincs are cheap insurance and he knows to replace them if there is any doubt. To Rob's point, the "neighborhood" can really dictate their condition. I have seen the difference in lifespan depending on which saltwater marina/neighborhood the boat sits in.

Anthony Warren
1999 28' Albin MadMoney

[Norseman]

I dock my boat in brackish water at a residential canal with few if any boats plugged in. (I got a solar panel, hardly ever plug in these days.)
Engine zincs last about 9 months, some longer.
External zincs about the same, but next time I will use aluminum anodes underwater.

[Bluewater]

Anthony and Norseman - thank you for the data. I’ll be checking the zinc status in three months, I think. My wife says that I if didn’t use the boat then the zincs would last much longer....... but that’s not going to happen.