>> I propose a ground strap at least, from head to cylinder body,
>>neutralizing any electrical imbalance. If nothing else it seems to me
>>it would cause pitting around elect. connection.
>
>I think this trick works only if the current flows in the right direction.
>Saltwater boats use it to protect their propellors etc. from galvanic
>corrosion (not from chemical saltwater corrosion as I recall). A current
>does inhibit galvanic action... but a current in the wrong direction
>*accelerates* the galvanic corrosion!

Basic point was, I have a hunch that a simple ground strap from heads
to cylinder, wouldn't help, and might even hurt, by promoting current
flow in the wrong direction. Maybe if you could somehow put a battery
and resistor, in a circuit including the head and cylinder (if those
two are indeed isolated), and so created an electrical potential in the
right direction between head and cylinder, then it might have some positive
effect (no pun intended) (well, not much).

Any physical chemists out there? They would know far more about the
validity of this effect, if any. Of course, I think my 6-year-old son
also knows more than I about galvanic corrosion sometimes...  :-\

    _______
   /\ o o o\         Steve Maher   smaher@gi.com   75461,1717
  /o \ o o o\_______   San Diego, California
 <    >------>   o /|
  \ o/  o   /_____/o|      '80 VW V6anagon
   \/______/     |oo|        '66 Mustang Coupevertible
         |   o   |o/       '89 Son Sherwin
         |_______|/
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