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 Electric fuel pump swap 
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Post Electric fuel pump swap
Just got a brand new 670cc 22hp predator. I've read all the problems related to fuel starvation at wot and am planning on putting an electric fuel pump. Can't find much info on this install. Do I need to remove the existing pulse pump or do I leave it hooked up and install the electric pump to help it? Thanks.


Thu Apr 05, 2018 9:44 pm
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Post Re: Electric fuel pump swap


Fri Apr 06, 2018 4:21 pm
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Post Re: Electric fuel pump swap
Thanks flint87.. ive been looking at the mr gasket 42s. Says it puts out 2-3.5 psi. will That be sufficient to run a gas tank on the floor of the boat? Will there be an issue with flooding or does it need to be regulated?


Fri Apr 06, 2018 5:06 pm
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Post Re: Electric fuel pump swap


Fri Apr 06, 2018 5:52 pm
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Location: West Monroe, LA
Post Re: Electric fuel pump swap
I recommend the facet over the Mr gasket, and the cube has been replaced with the posi-flow. There's one in 1-4 psi flavor, which would handle that engine and still not overpressye the float seat. I think the one you're looking at would be fine as well, I just don't like the Mr gasket pumps for being 5 miles from nowhere and relying on it.

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Fri Apr 06, 2018 5:57 pm
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Post Re: Electric fuel pump swap
I appreciate all the info guys. Thank you.


Fri Apr 06, 2018 6:34 pm
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Post Re: Electric fuel pump swap
Which do you recommend? The posi-flo or the cube?


Fri Apr 06, 2018 7:25 pm
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Post Re: Electric fuel pump swap
I had a cube for 3 years, it's now my spare (in a ziploc in my tool box) and I have a posi-flow. The posiflow is a newer model, don't know if they changed much between it and the cube. Both have been fine for me, but I only have about 40 hours on the posi flow, so don't know if it's gonna last as long. I see no reason it shouldnt.

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Fri Apr 06, 2018 8:28 pm
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Post Re: Electric fuel pump swap
I think I'm gonna go with the facet you recommended. Just curious on a mounting location. I'm going to be running a tank on the floor of boat with probably 6 feet of line. Is it the length of line that matters or how high the pump is mounted above the gas tank?


Sun Apr 08, 2018 7:58 pm
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Post Re: Electric fuel pump swap
My pump is mounted 6 inches from my fuel tank, then about 7 ft of fuel line, then the bulb, then another 2 ft of fuel line to the carb. I have a filter on the inlet side of the fuel pump, and sometimes run a plastic one somewhere between the bulb and the carb. Currently isn't one there, but it's good to have one to catch any crap if the fuel line starts separating so it doesn't get into the carb. When I had the cube before I switched to the posiflow, I had the same setup, except I had about 16 ft of fuel line between the pump and the bulb. Never had an issue. It's wired to my key switch. Pump the bulb 3 or 4 times to make sure the pump has fuel in it, then turn the key on, let it finish priming the line, then crank it up. The pump will do it by itself, but I typically don't run it without pumping the bulb a little first. Never had a fuel issue on the old kawa, nor the current fully modded briggs.

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Sun Apr 08, 2018 9:20 pm
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Post Re: Electric fuel pump swap
I'll add, the bulb isn't a necessity, and I used to not run one, either. Just kept it in the gun box for emergencies.

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Sun Apr 08, 2018 9:22 pm
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Post Re: Electric fuel pump swap
Not sure if mounting the pump 6 inches from my tank will be an option unless I put it right by the transom..i was trying to avoid too much weight in the back of the boat..id have to find a way to strap it down, I wouldn't want it kicked or bounced around pulling on the fuel line to the pump.


Mon Apr 09, 2018 8:48 pm
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Post Re: Electric fuel pump swap
Just giving you an example. And I have mine zip tied to the fuel tank.

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Tue Apr 10, 2018 4:43 am
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Post Re: Electric fuel pump swap


Wed Apr 25, 2018 8:55 pm
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Post Re: Electric fuel pump swap
From my duckhuntingchat build thread:

Quick update - for those who don't feel like reading above ^^^ I have a 15x42 tracker with a stock predator 670 MM. I took the boat out on a river by me last summer and it ran flawlessly. Ran probably 2 miles with a 700 pound load up river and no issues. Duck season comes around and the first few runs out I had the motor running about 3500-3600 RPM (max is 4000 w governor). Each time the motor bogged down and shut off about 80% of the way to the blind with about a 500 pound load (2 guys and gear). I'd have to wait about 30 seconds, choke it and run the rest of the way to the blind with it 1/4 choked. When getting back to the dock, same deal. Either way, it always started up and ran with choke so I knew it was a fuel starvation issue.

I remember reading how the fuel pumps for these engines are awful, so I ended up buying an electric fuel pump. I cleaned the carb and no issues with the jets. Put some startron in with my gas to help stabilize it. Ran the fuel pump wiring to my bus bar and an available switch in my box. I didn't want to wire it to the hot wire from my key box just because I don't feel like having to solder it when I go to sell this boat/engine. Zip tied the pump to my gas tank, and ran it like this: Tank > Pump > Bulb > Carb Intake (bypassed the stock fuel pump altogether). I plugged off the mechanical fuel pump hoses and left it connected in case my electric one fails and I have to hook it back up in the field.

Anyways, I adjusted the carb idle screw to run little hotter because it kept shutting off on me. Ran for about 10 mins full throttle and no shut offs, came back to idle without any issues and would stop/start/idle fine after this fix. The one issue with this fix is I need to remember to shutoff the fuel pump switch after I'm done or I'll flood the carb or run out the battery. This is when it would be ideal to have wired this to the key box, but whatever. It's quiet, but loud enough for me to hear it running and remind me to shut it off.

Materials - $1 for 2 hose clamps, $3 heat shrink, $3 dielectric grease, $15 for 2.5-4PSI Electric Fuel Pump

Pump:


Wed Aug 29, 2018 1:01 pm
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Post Re: Electric fuel pump swap
Aircraft Spruce makes a 1.5 - 2.5 psi pump which is what I put on mine.

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Wed Aug 29, 2018 1:36 pm
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Post Re: Electric fuel pump swap
I mounted the pump on the transom of an 18 foot boat with the tank up front with no bulb just the fuel line and have not had any problems with the pump being in the back. It has close to 16 feet of line before the pump and works good. Been like that for at least 4 years.


Wed Aug 29, 2018 5:59 pm
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Post Re: Electric fuel pump swap
Good info


Wed Aug 29, 2018 10:16 pm
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