The Cam Covers on my 2004 S Type 3.0 have seriously corroded but are not yet completely dead. Replacements are virtually impossible to find, either new or second hand. It is apparently an electrolytic problem and I've been told that a Sacrificial Anode may prevent further deterioration but neither my mechanics nor I have any idea how to implement this. Grateful if anyone can shed any light on how to do this!
Many thanks, Michael

 

You'll be hard-pressed to find a metal that is anodic to magnesium. I think it sits at or near the bottom of the galvanic chart.

 

I didn't realise that, thank you - would earthing the covers be worthwhile, do you think? Thereby creating a bypass for the voltage which is surely responsible?