Hey guys,
So my freshly rebuilt 509 I hope to drop in the boat this weekend but I want to plan out my fuel pump, I have a Holley inline pump that will be replacing the Cool-fuel unit. I am aslo going to return back to the tank and not the fuel filter housing so I am eliminating the fuel cooler as the tank with 100 gal will never heat up as I am on a small lake so run time is 20min to an hour at a clip.

My question is where are you guys mounting the fuel pumps? I have a new Harden Marine billet fuel filter canister with 1/2" NPT female ports, I plan to run -8AN from the tank to the housing and then to the fuel rails and into the regulator. From the reg back to the tank -6AN as my boat will be in the 550hp range so this should provide more than enough fuel.

I have seen them all over the place...most mount it where it most convenient. If you were trying to stay within USCG specs....then it would be mounted on the engine and the line from the pump to carb/fuel rail would be a hard line...but we all know thats not always possible. As long as your running quality fuel lines you should be fine.
Just keep in mind...with an electric fuel pump if you have a flex line on the output side...and it breaks....pump will continue to run flooding the bilge. Less likely to happen with a hard line.
If the supply line from tank to pump breaks then the anti-siphon valve (assuming you still have one) should stop the flow of fuel and motor will just die out.

mount it as low as you can so it doesn't have to fight pulling fuel up hill, I would still recommend running a fuel cooler

I have mine on the stringers. As you can see I return right before the filter. You want your return hose the same size or preferably one size larger not smaller.

Returning back into the supply line like that I understand why a fuel cooler is necessary but I would think going back into t a 100Gal tank it wont be as critical? Problem I have it the fuel filter is mounted up higher than I like I may have to look into relocating my fuel filter as well but my engine bay is quite tight in a Baja 252. The pain in the ass is since my Holley HP is on B/O im going to be running on a carb until the fall when I switch over to the Holley EFI so ill be doing things twice!
I think I modify the cool fuel bracket to house the new inline fuel pump but I don't think I can adapt it to the existing cool fuel heat exchanger.

I mounted my Aeromotive pump on the Cool Fuel bracket putting the inlet below the crank centerline - about as low as I could get it. I didn't have anywhere to mount the pumps in the bilge so I made do with the original bracket. Might be pain to remove if the pump goes bad, but with how much it cost, it better last a long time!

I went with a Holley and yeah not cheap either, I did a complete Holley system but the HP ECU being on B/O is killing me. Holley is making good for the delay by sending me a free 850CFM carb and a big discount on the ignition controls to go carb for the interim.

Now that I am thinking about it the cool-fuel exchanger is copper so if I thoroughly flush it out to rid it of any fuel I can braze on new NPT fittings and adapt it to my new fuel system. I have to look into this but I don't see why this cant work. Anyone know if these things are restrictive and should it be on the suction side of pressure side of the pump? If memory serves me correct the exchanger is on the pressure side of the pump to help cool the heating effect from the pump too.

Smitty would probably know the details, but if my memory is correct, it was pretty small.

I run the dominator 160 GPH pump on mine....mounted under the engine on the stringer. I don't run cool fuel or any of that stuff just return to the tanks and I've never had an issue. Don't have any pics handy...It's a roots blown 540 with holley EFI on it if that helps....FYI if you don't run the holley inlet and outlet filters on those dominator pumps anyway it voids the warranty...I had to buy them at the same time for the warranty to be valid not sure if that's still a thing or not but just throwing it out there.

I'm in the middle of this right now as well, does the fuel/water filter go before or after the pump? Its best for the pump for it to be before but Ive also read you want the minimum between the tank and pump. Currently have it as tank > pre filter > pump > post filter > fuel/water separator > engine


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