Bennett Trim Tab pitting

[Fossil Fuel]

Hi all, I'm getting excessive pitting on the Stainless bennett tab plates. The coating came off a few years ago so I cleaned that tabs and Installed a button zinc on the top of the tab plate. The mercathode is working and the drives seem to be protected OK. The drive zincs are working about right. The tabs are very active. They are not bonded as the screws are not through bolted. I'm thinking a bigger Zinc bar rather than a button? BTW Bennett customer service is the worst in the industry. I've been trying to get a Part ## for replacement plates for 6 weeks all I get is excuses..May have to Fab myself....

Thanks

 

[GSENT]

Fossil,
Zinc's will not work unless they are bonded to your DC electrical system. One of the screws should be a machine screw that thru bolts and should have a bonding wire (#8 copper) connected to the negative system.
All underwater metals must be bonded together, no exceptions.

 

[Nate]

Are you painting them with bottom paint? There is a zinc that's available that attaches where the ram attaches to the plate. I don't put zincs on mine and they have not had any pitting but my last boat would get pitting pretty easily.