Squeeze bulb goes flat

[jeffkujath]

I have 140 hp 1992 Johnson. After running ~1/2 hr squeeze bulb goes flat at all engine speeds. Must keep fidling with it / trying to force it open a bit to keep some gas moving to engine or stalls.<br /><br />Does this sound like it could be caused by fuel pump being bad? I have changed bulb, made sure vent line is open, gas uptake not blocked. <br /><br />Basically wondering if fuel pump goes would collapsing bulb be a result?

 

[fireman57]

Re: Squeeze bulb goes flat

Make sure the vent is open on your tank. You might also check out the thread of 85 hp fuel bulb collapses.

 

[Texasmark]

Re: Squeeze bulb goes flat

One additional problem, if the above are unsuccessful is something that happened to me once.<br /><br />I had a built in tank and used some kind of fuel treatment for storage that must have been an alcohol base and absorbed water in the tank. It made a big gooey blob that got lodged in the fuel line.<br /><br />With your bulb collapsing, it is telling me that you have suction from your fuel pump. It is sucking on the hose but you have a restriction toward the tank, from the bulb. This is putting negative pressure on the bulb (vacuum) which is collapsing it. Otherwise it would suck fuel from the tank and the bulb wouldn't collapse.<br /><br />Mark

 

[jeffkujath]

Re: Squeeze bulb goes flat

I know vent is open and working.

 

[Texasmark]

Re: Squeeze bulb goes flat

One additional problem, if the above are unsuccessful is something that happened to me once.<br /><br />I had a built in tank and used some kind of fuel treatment for storage that must have been an alcohol base and absorbed water in the tank. It made a big gooey blob that got lodged in the fuel line.<br /><br />With your bulb collapsing, it is telling me that you have suction from your fuel pump. It is sucking on the hose but you have a restriction toward the tank, from the bulb. This is putting negative pressure on the bulb (vacuum) which is collapsing it. Otherwise it would suck fuel from the tank and the bulb wouldn't collapse.<br /><br />Mark

 

[jeffkujath]

Re: Squeeze bulb goes flat

Thanks Texasmark. I just needed to get pointed in the right direction (towards engine or tank) to feel confident I can solve this

 

[ezeke]

Re: Squeeze bulb goes flat

The bulb collapse indicates that everything on the engine side of it is working as it should.

 

[Texasmark]

Re: Squeeze bulb goes flat

One more thought. If you have an inlet screen on your fuel tank pickup it may be clogged and it may be with such gooey crud as I had stuck in my fuel line that I mentioned.<br /><br />Something is blocking the line and allowing the pump to pull a vacuum. Fact man, you just need to find it. I would say that you had a defective bulb, but you said you changed it and the problem remained.<br /><br />HTH.<br /><br />Mark

 

[StratMan290FS]

Re: Squeeze bulb goes flat

I had this problem on my old boat once, which had removable tanks and after trying some different things i just replaced the bulb and fuel line, never had a problem after that. I guess this is the lucky fix and may not be your problem, jsut thought id drop that in especially if your bulb is older and possible dry-rotten a tad.

 

[BF]

Re: Squeeze bulb goes flat

Ditto what is said above... fuel pump is working OK, problem is either with the hose or the tank. You say:<br /><br />

I have changed bulb, made sure vent line is open, gas uptake not blocked.

If the tank is vented, and the gas uptake really is open and not blocked, then the problem is between the bulb and the uptake. One thing, if you have loose crude at the bottom of your tank, it could be that as gas is being drawn, crud is sucked against the uptake and progressively blocking it. Then if you shut the motor down (stop the vacuum), the crud would fall off the screen and all would appear OK on inspection.<br /><br />Is this a portable tank? If so, it's easy to borrow another tank and hose. Use your hose on borrowed tank, and then their hose on your tank.... you should be able to figure out where the problem is.

 

[perkdp]

Re: Squeeze bulb goes flat

Where's the first screen/filter/fitting between the bulb and the gas? Flakes of trash or rust are likely, gradually being sucked into that location restricting the gas flow to the bulb. <br /><br />Then when the motor is not running the trash falls back into the tank...<br /><br /><br />When the bulb collapses, does it expand again if you take the gas cap off ?

 

[cddetelich]

Re: Squeeze bulb goes flat

I have had several different motors/boats where I have replaced bulb with aftermarket bulb and then had fuel starvation issues during season-low flow, etc. Two different mechanics told me to stay away from aftermarket bulbs-spend the money and buy one made by one of the engine manufacurers-Bombardier, Mercury, Yamaha, etc. I did this twice and the problem was solved instantly. Now, I replace bulb every year and I only buy name-brand.

 

[Dhadley]

Re: Squeeze bulb goes flat

We've never really established that this is a built in tank or not. If it is, I'd be looking at the anti-siphon valve.