Electric Fuel Pump

MMHagler

Seaman
Joined
Apr 10, 2011
Messages
72
Put a new electric fuel pump on my 302 Ford. I asked for help last week and was told I probably needed a pump. Guy told me at the parts store to cut the line after my water/fuel separator and put the new electric fuel pump between there and the carb. I did that wired it directly to the battery took my boat out,it quit as soon as I got it on plane so now I am not sure it was the pump I waited a minute started it back up brought it home and the fuel pump was shaking,kinda warm and wouldn't shut off. Any help? Thx
 

djmakko

Petty Officer 2nd Class
Joined
May 9, 2011
Messages
134
Re: Electric Fuel Pump

You have the pump connected directly to the battery?if so, thats your problem electric pumps should be connected to an oil pressure switch or a relay so it shuts off/on when not need it. i dont have experience on a Ford Motors the pros should pitch in shortly.
 

boatguya1

Chief Petty Officer
Joined
Apr 24, 2009
Messages
444
Re: Electric Fuel Pump

You have the pump connected directly to the battery?if so, thats your problem electric pumps should be connected to an oil pressure switch or a relay so it shuts off/on when not need it. i dont have experience on a Ford Motors the pros should pitch in shortly.

As far as the engine running goes electric fuel pump hooked directly to batt will work fine. Safety wise on the other hand it is no good.

If you are trying to suck fuel through the old pump that may be the problem.

As posted above electric fuel pumps should be run off an oil pressure switch, motor stops=pump stops=good.

Also only marine approved fuel pumps should be used.
 

180shabah

Rear Admiral
Joined
Mar 26, 2005
Messages
4,995
Re: Electric Fuel Pump

"the guy at the parts store" is going to get somebody killed - YOU....

How did you determine that your existing pump was bad?

Why not replace the existing pump, rather than compromise your fuel system with some back yard hack job?

What problem are you trying to cure, and what troubleshooting have you done so far?
 

MMHagler

Seaman
Joined
Apr 10, 2011
Messages
72
Re: Electric Fuel Pump

My boat runs but like I wrote this week under load it quits. I was told it was a fuel problem and could probably use a new pump so I purchased a new electric pump. I removed the arm and plugged the holes in the original pump then bypassed it with the new pump. I'm asking for help because I don't know whats wrong and trying to save money by doing it myself. The battery was right there so I hooked it direct. My 1st post was under 302 Ford and most thought it was my pump.
 

180shabah

Rear Admiral
Joined
Mar 26, 2005
Messages
4,995
Re: Electric Fuel Pump

Hadn't read the other post. Now that you have two for the same issue that will be an on going issue.....

Two posters suggested testing your fuel pump, for pressure and vacuum. I did not see a response where you stated the results of testing.

You could be sucking air, could be a clogged vent, could be......

read here
http://forums.iboats.com/mercruiser...ow-testing-your-boats-fuel-system-283269.html
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,363
Re: Electric Fuel Pump

I removed the arm and plugged the holes in the original pump then bypassed it with the new pump. I'm asking for help because I don't know whats wrong and trying to save money by doing it myself. The battery was right there so I hooked it direct. My 1st post was under 302 Ford and most thought it was my pump.

from the tank to the fuel sep/filter then to the fuel pump, (mech or elec) ,then to the carb.nothing elese in between.
there is a anti-syphon at the tank, could be restricting fuel flow.
 

djmakko

Petty Officer 2nd Class
Joined
May 9, 2011
Messages
134
Re: Electric Fuel Pump

As far as the engine running goes electric fuel pump hooked directly to batt will work fine.

So how does the pump shuts off ,if it is connected directly to the battery? wont it be running all the time?
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
Re: Electric Fuel Pump

An electric fuel pump should only run when either the key is in start position or when the oil pressure switch detects oil pressure while the engine is running. It is for safety. You don't want the pump running in any other case for safety reasons. I would suggest just sticking with the original mechanical type fuel pump.
 

Chemdawg

Petty Officer 2nd Class
Joined
Aug 31, 2013
Messages
112
Re: Electric Fuel Pump

I installed an electric pump on mine, ran a wire from the pump to a switch, then grounded the pump. The switch gets power from the hot wire already up front. It turns off with the switch or when I turn the key off.
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
Re: Electric Fuel Pump

I installed an electric pump on mine, ran a wire from the pump to a switch, then grounded the pump. The switch gets power from the hot wire already up front. It turns off with the switch or when I turn the key off.
That is not the correct way to do it.
 

tinkerguy70

Petty Officer 2nd Class
Joined
Oct 12, 2012
Messages
190
Re: Electric Fuel Pump

I installed an electric pump on mine, ran a wire from the pump to a switch, then grounded the pump. The switch gets power from the hot wire already up front. It turns off with the switch or when I turn the key off.

That is not the correct way to do it.

No it is not the correct way, at the very least it should be wired through a relay.

Hey, take some advice from a guy who has already tried this route, get rid of those aftermarket electric fuel pumps and get the right replacement mechanical pump for the engine.
Trust me, you'll be chasing gremlins from those things forever. Just bite the bullet, spend the money, and buy the correct fuel pump for the engine. You'll be much happier (and safer) in the end and your boat will run a lot better.
Boats aren't much fun when you're constantly working on problems (that you created by trying to take a shortcut and cheap out) and they're even less fun when you are stranded miles from the dock with no help in sight.
 

Chemdawg

Petty Officer 2nd Class
Joined
Aug 31, 2013
Messages
112
Re: Electric Fuel Pump

Maybe that's the case. It's been running great for the last month.

I must have wired my pro street 70 camaro wrong too.

I didn't actually have a problem with my mechanical pump. Went electric like I did on my car. Just my choice
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
Re: Electric Fuel Pump

Maybe that's the case. It's been running great for the last month.

I must have wired my pro street 70 camaro wrong too.

I didn't actually have a problem with my mechanical pump. Went electric like I did on my car. Just my choice
Safety on a boat and safety in a car is a lot different. Just because it works doesn't mean it is right. In a car you have an open to air non-contained compartment. What happens if fuel or oil leaks in a boat? Good luck with your insurance when you blow it up. Stay away from my lake please.
 

Chemdawg

Petty Officer 2nd Class
Joined
Aug 31, 2013
Messages
112
Re: Electric Fuel Pump

Good point on that. What would be a good way to wire it if you chose to go electric?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,426
Re: Electric Fuel Pump

Good point on that. What would be a good way to wire it if you chose to go electric?

it is wired with a relay, an oil pressure switch and a run to the s-terminal on the starter.

when cranking you get fuel, and only when there is oil pressure do you get fuel. plenty of threads on the proper way to wire an electric fuel pump on a boat. which, by the way is the way most auto makers wired their electric fuel pumps on the cars.

the oil pressure switch is a safety to only allow the fuel pump to run when the engine is running.
 

MMHagler

Seaman
Joined
Apr 10, 2011
Messages
72
Re: Electric Fuel Pump

Back to my original problem. I will hook it up with safety in mind it was a handy spot to try and fix the boat issue. I emptied the water separator and hooked the pump up to power and it wouldn't draw a drop of fuel from the tank so I pulled it off the carb put my thumb over the gas line and it filled the separator and started pumping gas into the jar. Filter is not blocked at the carb. Anything? Thx
 

SangerDX

Cadet
Joined
Sep 26, 2013
Messages
13
Re: Electric Fuel Pump

It would be a good idea to test the fuel pressure the electric is putting out, my brother converted and he had to put a regulator on to get the boat running properly. It seemed fine at first, but he kept having problems until he dialed the pressure back to match a mechanical pump.
btw, he did hook to the oil pressure switch too; you don't want a high powered electric pump throwing fuel at a closed space.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Electric Fuel Pump

Electric fuel pumps on a boat should be wired the same way they are on a car. If the engine dies so does the pump. Look -- engines in boats can die for any number of reasons. If the engine dies and the pump keeps running you run the risk of loading the engine or the engine bay up with fuel. You hit the key to restart and "kaboom", you, your passengers and your boat all become cinders. Should you have an engine bay fire you definitely do not a fuel pump running to feed that fire. And don't try to convince me that you would remember to turn the key off. Electric pumps can be run safely -- but they need to be plumbed and wired safely.
 

Volphin

Lieutenant
Joined
Jun 5, 2011
Messages
1,405
Re: Electric Fuel Pump

I went with a Holley Marine electric fuel pump (vane driven). Perfect psi for carbs. Runs only when the key is in the run position.
 
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