Fuel Bulb - 1990 150 hp V6 ETLD

[tuccimf1]

New fuel line, new gaskets, new fuel bulb....When the motor is off why does the fuel bulb when you pump it up goes soft with in 2-3 minutes? I also have to continuously pump the bulb when the motor is running. Why would this happen? We are running the direct line out of a 5 gallon gas tank.

Also there is a small hose loose. Where does this go? This is underneath bottom carb. See photo attached.

[99yam40]

if you are not seeing gas coming out of the lines ,filters, carbs, etc. when you pump the bulb
then I would be checking on the fuel pumps

[DennisG01]

The hose looks to be about the size of the hose that would connect to the nipple on the plastic intake... the thing that is not there in your picture... hence the reason the tube isn't connected!

You may have the fuel bulb installed backwards? There's an arrow on it to show the proper direction fo fuel flow. Or, it's been noted that if the bulb is angled downwards that it may not work properly - I have no actual experience with that, other than what I have read. But I suppose it could, in the right circumstances, prevent the check valve from operating properly.

[ausnoelm]

Do you have to pump the bulb to keep the motor running? it's not exactly clear if that's what you mean. Is the bulb a genuine one, or a cheap no name?

[fairdeal]

When the motor is off why does the fuel bulb when you pump it up goes soft with in 2-3 minutes?

Nothing wrong with that, the bulb isn't designed, or expected, to remain 'hard' indefinitely.
It only needs to be able to 'work' when you need to squeeze it.

I also have to continuously pump the bulb when the motor is running.

Then there is nothing wrong with the bulb, lines, tank, etc -
the likely problem is,
the engine's own fuel pump is bad.

[DennisG01]

Fair... but it shouldn't go soft THAT quickly, right? I mean, shoudn't the check valve in the bulb prevent that? I suppose having the bulb mounted backwards isn't the problem, but if it was mounted facing down? That said, I've probably never checked the bulb that quickly after turning the engine off.

ButI agree that having to continually pump the bulb to keep the engine running is due to failing engine-mounted low pressure pump(s). In that case, even if the bulb was mounted facing down... I don't think it would cause the need to continually pump the bulb since once the engine is running, the bulb is not needed at all.

So... probably have at least LP pump issues and should at least correct that, first. You can test them for pressure/vacuum (see your service manual for the exact procedure), if you want to.