Installation of electric fuel pump 2003 90 HP Johnson OB

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Apr 26, 2011
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Want to replace primer bulb (been a pain in the lower unit) with an electric fuel pump mainly for initial priming. Fuel tank under center console and priming with hand bulb doesn't work well, they seem to not last one season. Should I turn it on and leave it on or just use for priming and let motor pump pull through electric pump while running? Going to install in series with the existing line with no valves. What is the normal PSI of the engine pump while running? The one I think I want has a discharge pressure of 2 - 3.5 PSI @ 15 GPM w/ 1/8" NPT fittings and is Coast Guard approved. Any thoughts?
 

alldodge

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Not an outboard guy but this link lets you know how to do it. The issue is your motors pump will have a hard time pulling fuel thru the electric pump. You don't want to leave it running unless it is connected to the motor, so if the motor dies so does the pump.
http://forums.iboats.com/forum/engi...-fuel-pump-instead-of-primer-bulb-on-outboard

This one talks about using a momentary switch
http://forums.iboats.com/forum/engi...787-o-k-to-put-electric-fuel-pump-on-outboard

Hope outboard guys come in to comment, good luck
 

alldodge

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Just thought of something that could expand on what Faztbullet listed in the previous link and pic below. Instead of installing a check valve where shown, just place your primer bulb inline where the hose is shown. The primer bulb has the check valve in it.

primer.jpg
 

GA_Boater

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There are 1000's of boats running around set up just like yours and they don't have this problem.

I'm going to guess the check valves in the fuel pump are at fault. Failing check valves can allow fuel to drain back to the tank and can make every start like beginning again after running out of gas with a lot of squeezing to fill the hose, pump and float bowl.

Diaphragms are changed often, but the check valves are often overlooked. Just a thought.

How she running other than the bulb issue?
 
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Scott Danforth

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is it your bulb not lasting thru the season? buy a better quality bulb. The bulb on the fishing boat is 28 years old. its getting a bit stiff, however it still primes the system every time.

if it is not holding prime, check the check valves like GA mentioned.
 
Joined
Apr 26, 2011
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is it your bulb not lasting thru the season? buy a better quality bulb. The bulb on the fishing boat is 28 years old. its getting a bit stiff, however it still primes the system every time.

if it is not holding prime, check the check valves like GA mentioned.

I have tried a couple of bulbs, what one would you recommend?
 

Fed

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Leaky check valves can't drain the fuel bowel.

You might want to try holding the primer bulb vertical with the arrow pointing up, once fuel reaches the primer bulb it will pump to its maximum.
Installing close to the tank is better as they pump fuel much better than they suck air.
 

GA_Boater

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I'll tell my valves not to drain the hose the next time they go bad. But they were 50 years old.
 
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tommarvin

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Somethin aint jiven here, you don't need to add an electrical fuel pump it worked fine without it, something broke and changed the fuel delivery.

Order a fuel pump rebuild kit from Iboats and rebuild it and change the check valves to if they don't come with the kit,and be done with it.
 

James R

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Are you buying genuine BRP priming bulbs and are you using Stabil Marine in your fuel. If not you have your answer.
 

fhhuber

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With cover off the engine... and engine down in normal running position...

Pump that bulb up till its stiff then squeeze HARD while looking at your fuel pump and hoses.

Simple pressure leak check. Cure any leaks found.

I just replaced every hose in the fuel system because I was tired of chasing tiny leaks.
 
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