Adding electric fuel pumps on outboards...Need advice please.

I would like to replace the squeeze bulb on my pontoon with an in-line electric fuel pump so I could prime it from the console...I'm thinking a momentary push button switch,to just run it a few seconds when needed,which would require the pump to be a "flow-thru" type with no resistance to the gas flow when the pump is off.Otherwise,the cheap universal pumps they sell at AutoZone,which are NOT flow-thru,would just have to run continuously.Now,would that be a problem to have it that way? Could it possibly over-power the carb floats and flood the engine,or any other issues to worry about? If so, Where could I find a cheap flow-thru type of pump in a low pressure version? I cant seem to get much detailed info on the dealer's websites.

first off what sized engine is it?

I think if you buy a continuous pumping fuel pump it could also starve the motor of fuel if its not pumping enough

It is a Yamaha 225 2-stroke

I found one from Airtex that is a flow-thru design made for boats and they said it was the right one for this application...to be used momentarily as a priming device only,then allows the engine fuel pump to take over.Got one ordered now from AutoZone.

with the price of outboard engines now my question would be if its not broke WHY fix it. The primer bulbs
have been used for at least 50 years that I know of. Does the pump you ordered have a check valve?
After all it has to hold pressure while allowing the engine pump to suck thru it. Its just too iffy
for my liking. Hope it works

Johnny

with a prime only pump you should be fine.

this is why I asked what engine, merc and johnson/rudes can be converted as can the non hpdi yammie 2 strokes so that you can eliminate the engine pump.

like this, my johnson 175 fast strike.

How long do you let it prime for and what is the part number for that pump? I need to replace the primer bulb in mine as well as the fuel line and I might convert to this while I'm there. I want to get the splash well cleaned up of clutter like that...

Any auto store will have a low pressure electric pump. Mount it close to the fuel pick up and you will be fine, also won't get near as much vibration as mounted to the engine. I have been doing this for 30 plus years on carbed OMC's and Mercury's. Never a failure.

You'll likely blow out the diaphragms on your low pressure pumps. There is a sticky over on BBC that has an example of replacing the low pressure pumps with an electric pump.

http://www.bbcboards.net/yamaha-motors/249083-no-more-lift-pumps.html

I have to find someone to do this on mine

The whole reason I'm doing this is because on my pontoon boat, the fuel tank is located under the deck,inside the center pod (actually it's a tri-toon),and the primer bulb is in a difficult location for this old timer to reach.
Now again,this add on pump will be for priming purposes only.
The one I chose is the Airtex mod.E8251,which was recommended to me by the manufacturer's Tech Support guy for this purpose.It is a low-pressure,low-volume,flow-thru design.Not intended to replace the original pump on the engine,but only to get fuel there long enough to get the engine started.
Now Here's the trick I decided to use in order to prevent any starvation issues...
I will install a "T" fitting in the fuel line AFTER the squeeze bulb,and leave the squeeze bulb in the system. Then a short piece of hose from that "T" to the "primer" pump,then another hose out from the pump,then into another "T" going back into the main line,to feed the engine.
In other words,the new pump will be installed into a "bypass" loop,going back into the main line to the engine.Now there are TWO paths for fuel to flow thru,and the squeeze bulb check valve will close during the momentary priming of the lines,then re-open once the motor starts up.At this time,the electric fuel pump is NOT running any more,and the engine is pulling fuel on it's own,as it always has.Fuel is now passing thru BOTH the squeeze bulb AND the auxiliary pump,and will take the path of least resistance.
The new pump will be on a momentary push-button switch,and only allowed to run for a few seconds when priming is needed.
Now my question is...Is there any reason why this wouldn't work?

I doubt anyone has tried anything like that before, least I never heard of it but ya still gonna get some opinions 'bout it.. ya may need some type check valve on tha tank side of tha electric pump, unless tha pump itself had one, donno?.. gl n hope it works for ya.......

jed the only thing I would question about it is the loop, why not just put the flow thru before the bulb and leave out all the extra connections.

not sure why you need the loop is all.

the momentary is the right way to wire that and just before the bulb should be good to go.

only other way I could think of is a seperate fuel line at the tank and T into the line after the bulb but again you have extra connections that I doubt are needed.

placed before the bulb the bulb check valve would do it.

UncleJed, Is your 225 fuel injected? I'm assuming it is. If so you shouldn't even need to squeeze the primer bulb to start the engine. There should be plenty of fuel already in your VST tank on the engine ..where the high pressure injector pump resides. On my bass boat with a Yamaha 225 VMax I never have to prime the bulb, just crank and go. Maybe your lift pumps have more trouble than mine pulling fuel from the fuel tank, not sure. Have you tried cranking without priming with the bulb or are you just assuming you have to?

this would work but don't know 'bout how and/or why tha "loop" thingy....