Hey guys,
>I don't believe that the working fluid is metallic sodium
Well if it were that would be awesome but a bit dangerous if there were leaks.
Never seen leaks in those early iBook G3s or even the G4s.
So I'm thinking phase change or silicone based fluid. I'm not thinking anything under pressure.
There were leaking problems in the Power Mac G5s. These were the fastest Dual G5s and ran at 2.7 GHz:
http://www.xlr8yourmac.com/systems/G5_coolant_leaks.html
These seem to work like a conventional auto type coolant system and that makes sense since they were designed by an automotive company.
The earlier Single/Dual G5s use heat pipes of the same design as those in the laptops.
In Googling heat pipe this:
http://en.wikipedia.org/wiki/Heat_pipe
says the fluid was
" such fluids include water, ethanol, acetone, sodium, or mercury"
Can't imagine that the latter two would have been used because if that were the case there would have been a warning label on the laptop. Re: the warning label on current high efficiency FLD lamps and the label on the LiIon batteries.
All of the iBook G3s and G4s seem to have the same type of heat pipe.
So since you're deconstructing the laptop you should be able to easily tell what the fluid in there was. I would be interested in what you find.
Richard