Another fuel system setup question - fuel / water filter before or after mech pump?
#1
Another fuel system setup question - fuel / water filter before or after mech pump?
I'm switching from an electric to a mechanical pump, and I am wondering if I should run my line from the tank to the fuel/water separator first and then the pump, or go straight to the pump. I believe it went to the filter first when I got the boat and it had a mechanical pump on it. When I went to an electric pump I ran the line straight to the pump because I understood that those pumps are designed to push fuel rather than pull it, but I believe the mechanical pumps are a different beast. Does this make any difference? It would seem to be a good thing to have a filter in place ahead of the pump as long as it can pull the fuel through it without any problems. FWIW, it is one of the Holley 6-valve pumps through 1/2 inch lines.
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not...merc sucks fuel through the spin on fuel filter..carb models have a rock filter in the carberator also..(Qjet) i have also seen some efi with and with out in line fuel filters after the feed pump..
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Most Merc fuel/water filters are 4 micron, which is pretty fine. I use a 100 micron filter before fuel pump.
Last edited by Bawana; 06-01-2015 at 10:37 AM.
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Bud. I know for a fact that Holley fuel pump will pull at least 762hp worth of fuel through a stock Merc filter head/filter and a 3/8 hose with a little tiny pick-up tube and a whole bunch of NPT 90's all over the place. Not my setup but have been on the boat many times where it went to WOT and stayed there for 15-20 minutes at a time.
#10
Bud. I know for a fact that Holley fuel pump will pull at least 762hp worth of fuel through a stock Merc filter head/filter and a 3/8 hose with a little tiny pick-up tube and a whole bunch of NPT 90's all over the place. Not my setup but have been on the boat many times where it went to WOT and stayed there for 15-20 minutes at a time.