HPBCANADA.COM

Looks cool Dave
I would love to see an analysis of a 2.5 fuel delivery system with regards to flow restrictions.
I run a Bosch pump through a Merc separator with a 39psi regulator and a small fuel rail returning to the separator... Likely not the best HP way to go but it has fed my motor for what I do.
The question is what difference would it make if I ran a direct to the motor and return to the tank with the same pump???

If the tank is left properly with the fuel topped up or completely empty I've never run a water separator ever . One more thing to go wrong .
If the fuel is bought at a well used gas station that turns the tanks over often there should never be a problem. My thoughts have always been that you never see a car with a water separator EVER ( that I know of at least ) .
As well most boats on this forum are only in the water a max of two evenings so the condensing problems are at an extreme low percentage.

That being said if you use a high flow water separator like the one Dave has pointed out it wouldn't hurt a situation or set-up as long as it does flow that much with your particular fuel system .
Roughly .7lb per hour per HP ( to be on the safe side )
260 would roughly be 182lbs per hour
182lbs / 6.5 ( roughly the fuel weight per gallon ) = 28gph

http://www.diamondmarine.com/web_pages/ ... System.htm i think that gets explained here.

"The question is what difference would it make if I ran a direct to the motor and return to the tank with the same pump???"

The difference is only when the motor is not running the return line cannot dump fuel as fast as it needs to so the pump will start to cavitate which is hard on the bosh pump veins. I've ran it with a 10 Micron water separator for 10 years with no issue. My system will flow about 1ltr in 17/18 sec. No matter what I did last year with the Merc separator I could not flow any better.

Regardless of pressure, you need to flow a min of 1ltr in 14 seconds if you're going to turn approx 10k.

So since I may drag a couple times and want to spin a little more than 8200. I would rather spend the money than burn a block, it happens fast and when you don't expect it.

Also I boat on Georgian Bay a lot and sometimes fuel up at a marina so I can never be sure if the fuel has water in it so to me it's cheap insurance.

Oh and for James,

I'm only doing my part for the carbon foot print ...