Fuel pump is not getting gas to the engine or getting firm when squeezed

[rabyadam]

This weekend I couldn't get my boat to start...I squeezed the bulb, but it would not get hard, and it didn't sound like gas was getting through to the engine. I went out yesterday and bought a whole new bulb and fuel line as well as all new connectors (male and female for the gas can), and the one that connects into the motor. But still there is no pressure building when I squeeze the bulb.

The weekend before it was running and working fine, it always took maybe 5 squeezes at most to get it nice and firm. The arrow on the new bulb is facing the right way (from tank to engine), and my air intake on the gas can is open. I have read alot about holding the bulb vertical when squeezing (with arrow on bulb pointing upwards to the sky), but it doesn't seem to make a difference.

Any suggestions? The weird thing is that when I disconnect the fuel line at the motor (and leave conected at the gas can) it does build pressure and become nice and hard when squeezed, but loses the pressure when plugged back into engine.

Any info would be appreciated.

 

[Charlie61]

Re: Fuel pump is not getting gas to the engine or getting firm when squeezed

you are sucking air someplace what kind of gas tank do you have. you may want to reinstall all your gas fiting of from your gas tank

 

[carholme]

Re: Fuel pump is not getting gas to the engine or getting firm when squeezed

First of all, it would be nice to know what engine you are talking about. But if you get pressure when the fuel line is disconnected at the engine but not when you connect it, it sounds like the check valves in your fuel pump are not holding the pressure when you squeeze the bulb. Have a look at the valves and the diaphram.

Gerry

 

[pinellas50]

Re: Fuel pump is not getting gas to the engine or getting firm when squeezed

My neighbor is going through a similar scenario right now. He touched the fuel feed fitting coming out of the tank and it snapped right off. He suspects that fitting had cracked and was sucking air. He is still in the middle of the repair so I don't know if this was the root of his problems.

 

[rabyadam]

Re: Fuel pump is not getting gas to the engine or getting firm when squeezed

The Motor is a 40hp Mercury. It's an 80's model (not sure of the year off the top of my head).

I thought it was the gas tank as well, I was gonna replace the whole tank, but ya when I disconnect it at the engine, it holds the pressure in the bulb, but as soon as I reconnect at the engine, it becomes very easy to squeeze again....

It worked all summer, 3-5 squeezes max and it was firm

 

[Charlie61]

Re: Fuel pump is not getting gas to the engine or getting firm when squeezed

if it holds pressure when you disconnect from your carduretor may be leaking,if motor is up and you see gas running from the cards the floats not stopping gas from leaking, you may need to rebuild them

 

[Snowfish]

Re: Fuel pump is not getting gas to the engine or getting firm when squeezed

The primer bulb gets hard, when the line is disconnected from the motor, due to the check valve on the coupler. Automatically closes the end when disconnected from the motor.

The primer bulb only has one check valve to prevent gas from flowing back into the tank. But it can't draw, from the tank, unless something is blocking the opposite side. That's were the fuel pump check valve comes into play.

Carholme nailed it with "fuel pump check valve is not hold pressure". Since that's the case, the fuel pump is ready for a rebuild.

I just did this a little while ago. Inside of pump was pretty ugly.

http://forums.iboats.com/showthread.php?t=565991

I still need to clean the carbs. The ultra fine degraded check valves and bellows has contaminated the system. Boat runs fine, but will need to be addressed at seasons end. Unfortunately that's just a little over 2 months away.

 

[rabyadam]

Re: Fuel pump is not getting gas to the engine or getting firm when squeezed

First of all, it would be nice to know what engine you are talking about. But if you get pressure when the fuel line is disconnected at the engine but not when you connect it, it sounds like the check valves in your fuel pump are not holding the pressure when you squeeze the bulb. Have a look at the valves and the diaphram.

Gerry

I will take a look at my fuel pump when I get home tonight, I may just replace the whole thing and see what happens. Thanks.

New Liskeard eh? I grew up in Smooth Rock Falls, I was just in New Liskeard about a month ago (the first day of the forest fires actually, thought it was a cigarette butt that landed in the back seat, made my buddy climb to the back and look for it)

 

[Snowfish]

Re: Fuel pump is not getting gas to the engine or getting firm when squeezed

I will take a look at my fuel pump when I get home tonight, I may just replace the whole thing

A rebuild kit is not that tough. Just take your time. Study, lay out the parts, little by little, and clean as you go. Lots of little parts. You can do it! A rebuild kit is, more than likely, a lot less expensive than a brand new pump.

Oh, and new fuel filter too. Carb cleaning may be in order too. You'll know when you see all the black crud inside.

Be sure to let us know how it went.