Water and fuel filters: questions on fuel pressures/flow

[jtodd]

I've been looking at some water/fuel filters, and I'm having some doubts over the effectiveness of their abilities, or at least of the ones that I'm commonly seeing on eBay which seem to be of high quality (Racor).  Example - this Racor 777R has a heater in it, and the auction says it separates the water out by centrifuge.  That would imply a quickly-spinning rotor of some type. 
 
 http://cgi.ebay.com/ebaymotors/Fuel-Filter-Water-Separator-W-Heater-RACOR-777R_W0QQcmdZViewItemQQcategoryZ50466QQihZ010QQitemZ200057060528QQrdZ1QQsspagenameZWDVW

My question is this: I didn't think that even at a maximum of probably somewhere around .5gph that this would be sufficient to do any rotor-spinning, and it is unclear to me that there is any electrical activation of the centrifuge.  What, exactly, provides the energy to spin a centrifuge at a speed sufficient to get water and fuel to separate?  Will the fuel pump that comes on my 12/2 be up to the task?  Personally, I doubt it, so I have my doubts about this type of water separation filter.  However, I have not used one so I can't say if it works or not - I'm just guessing.  Can anyone with more than guesses chime in?

JT

[rmchambers]

It looks like they expect the centrifuge to be powered by the flow of the fuel.  I had a quick peek on the parker website and apart from being one of the flakiest websites I've seen it had no documentation on this particular model.

I'd keep hunting around to get a definitive answer but I think it's fuel flow powered in which case half a gallon an hour isn't going to get you much spin.

Robert

[Stan]

My dad taught me that if you take an old felt had and put it into the funnel when you're filling your fuel tank, it'll trap all the water trying to pass through it.  We used to fill our tractors from 45 gal drums which often had lots of water in them.  It works like a charm.
Stan