Priming a fuel injected OB?

[captnjack]

I have a virtually new 60hp fuel injected Yamaha 4-stroke on a 16ft RIB. This past weekend we set a weightbelt on the fuel line and pinched it. Afterwards we couldn't get it re-primed, the air just sloshed back and forth in the line. Eventually we raised up the portable tank and got enough fuel in the line to start the engine.

So I replaced the primer bulb. Even with a brand new bulb, priming didn't happen. I suspect this may be because there's no place for the air to go in a fel injected engine. I.e. the bulb can't push air past the fuel pump/injectors and there's no carburator to vent it off.

Anyone else had this issue? Is this an issue for all fuel injected motors? Do you just keep cranking it to prime the fuel line with its own fuel pump? I'm puzzled.

Thanks
Richard

[Erin]

The air goes somewhere, though I'm not quite sure where. I know it can take alot of squeezing on the primer bulb when the fuel lines are empty of any fuel. Have you made sure the new bulb is on teh right way around.

[captnjack]

The new bulb is installed the right way around. My extra fuel filter has a clear globe and I can see the air just sloshing back and forth in there.

Maybe I just didn't squeeze it long enough?

[bedajim]

Originally Posted by captnjack

The new bulb is installed the right way around. My extra fuel filter has a clear globe and I can see the air just sloshing back and forth in there.

Maybe I just didn't squeeze it long enough?

Open the bleed on the fuel filter or take the fuel hose off the engine end and prime it until the fuel comes out of the hose then stick it back on

[jyasaki]

Originally Posted by captnjack

So I replaced the primer bulb. Even with a brand new bulb, priming didn't happen. I suspect this may be because there's no place for the air to go in a fel injected engine. I.e. the bulb can't push air past the fuel pump/injectors and there's no carburator to vent it off.

Question is, what did you replace the bulb with? OEM? Or Tempo?

I had a Tempo primer bulb that new, out of the package, wouldn't pump air (much less fuel.) The bulb would compress, but would not re-expand. Add to that that every fitting had to be modified to work, and, well, never again.

Anyone else had this issue? Is this an issue for all fuel injected motors? Do you just keep cranking it to prime the fuel line with its own fuel pump? I'm puzzled.

I remember this being an issue with early FI cars, but I haven't heard of the problem recently.

Considering engines are shipped dry, and fueled once installed, I can't see this being a routine problem.

You've actually got 2 fuel pumps in your engine: a low pressure pump (the one that draws fuel from the tank to the engine), and a high pressure pump (that supplies the injectors with pressurized fuel.) So, the question is, which one isn't working? Perhaps you could start disonnecting things and see where you're losing pressure?

I'd think that there has to be some sort of vapor separator somewhere, else the motor would never be able to get raw fuel. But, I have no idea where it would be.

You can poke around on the Yamaha website and see if you can figure it out from the parts list. Go to www.yamaha-motor.com, select Marine, select Parts and Service, and there's a link for the parts list there. The owners manuals are also available on-line.

I looked, but was unable to find anything of use for your problem. You might have better luck than I did.

jky

[captnjack]

Originally Posted by bedajim

Open the bleed on the fuel filter or take the fuel hose off the engine end and prime it until the fuel comes out of the hose then stick it back on

That's what we ended up doing. Had to hold the check valve open to let the air out and of course you can make a mess with the gas if you're not careful (I did). Seems odd that there's no air vent.

I suppose its possible that more cranking was needed to pull the air out of 2 fuel filters and the line. I was diving at the time, my boattender couldn't restart. But I don't know how long he cranked for.

I will look and see if there's an air/fuel bleed on the LP pump or the on-engine fuel filter. Both the new and old bulbs worked fine uninstalled.

[ian parkes]

When i changed my fuel filter earlier in the year i couldn't get the thing to prime on the bulb at all .
In the end I turned the key and away it went sucking its own fuel through an empty filter no problem . i guess there was enough in the little engine filter to fire the motor up . It went weak for a second or two but thats all .
I don't suppose the yam is much different to the suzuki , they must have a pretty good fuel pump for the EFI.

[bedajim]

Originally Posted by captnjack

That's what we ended up doing. Had to hold the check valve open to let the air out and of course you can make a mess with the gas if you're not careful (I did). .

They did that with mine when it had its PDI to fill the primer bulb for the first time, he said it was common as the bulb needs fuel to prime the system "as he spat the petrol out"

[fast fred]

this is how it works, the bulb will pull air or fuel, which ever is easyest for it,
pluged in to the tank with a fresh bulb, you use your thumb on the moda side
of the fuel line, squese the bulb, to push the air out, then hold your thumb on the line, so no air can get pulled in, it will pull the fuel into the bulb, if ya go slow about it you can fill the line with out spillin any, then plug in to the moda
and prime away.