Actually, I've heard of this approach being used also to stop body rust
on cars.  Could be of interest to us folks.  I'd probably pay for that
:)

Sean

> 
>  Back in my past, we used to put this solar panel and a battery
> out in the wilds on pipe lines to prevent corrosion. A few milli-
> amps at a couple volts into the pipe would stop the material migration.
>  I don't own a water pumper but I've heard about them from some of 
> the other members. And the price of heads. 
>  What seems to be happening is a galvanic action caused by heat and 
> dissimilar metals. I don't think this would be happening if the heads
> were not isolated electricly from the block. 
>  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. 
>  This is just a thought guys, maybe some of you electron hounds can
> make something of it.     west
> 
>  of course if it works, you'll never know!
>  
> 
>