How Hard Can You Squeeze Bulb ?

[FillupD]

I have a 1976 55 Hp motor that will cut out if you don't squeeze the bulb. I searched on here and started trouble shooting and I kinda get stumped at the bulb hardness.
I can pump up my bulb (not running) and it gets pretty firm but if I keep squeezing it really hard, well not really hard, but pretty good pressure, it starts to go flat. Is it possible to push fuel through the carb needles? Should the bulb hold pressure so that it would be impossible to make it go flat?
I did this with both of my fuel line setups and started getting fuel out the exhaust by prop ( I think, it is dark so I thought it may be lube but it didn't leak there until I started looking at my fuel system.)so I am definitely getting fuel past needles but maybe I am squeezing to hard, or should that really matter?

Could this cause the low fuel situation on the water or shall I continue with the fuel pump. All hoses and fittings look good, Factory clamps anyway but I guess looking may not cut it when leak detecting.

 

[Daviet]

Re: How Hard Can You Squeeze Bulb ?

With out the engine running the bulb should be firm, no need to try to squeeze any harder. After the engine starts the bulb will go soft because the fuel pump is pulling fuel through it. If you think fuel pump is defective pumping the bulb will keep engine running.

 

[Joe Reeves]

Re: How Hard Can You Squeeze Bulb ?

If the carburetor isn't flooding which should be obvious, the fuel pump diaphram is cracked and is allowing fuel to directly pass thru it into the crankcase area.

(Fuel Pump Diaphragm Test)
(Two Hose Type Only)
(J. Reeves)

Note: This pertains only to the regular Two Hose type fuel pumps.

Leave the hoses attached to the fuel pump. Remove only the two screws that attach the fuel pump to the powerhead. Re-insert those two screws and install a nut to each of them so that the fuel pump is securely clamped together. With the fuel line attached to the engine, pump the primer bulb while observing the pressure/vacuum operating hole on the back side of the fuel pump. Should any fuel leak out that hole, the diaphragm is faulty.

If the diaphragm is faulty, the fuel pump will require rebuilding or replacing. Note that repair kits are not available for all fuel pumps, in which case replacing the pump would be necessary.

 

[daselbee]

Re: How Hard Can You Squeeze Bulb ?

With out the engine running the bulb should be firm, no need to try to squeeze any harder. After the engine starts the bulb will go soft because the fuel pump is pulling fuel through it. If you think fuel pump is defective pumping the bulb will keep engine running.

^^^^^^^
What he said...exactly.

 

[FillupD]

Re: How Hard Can You Squeeze Bulb ?

Thanks for your help,

I'll post back after my rebuild kit gets here and I get it put together. I'm glad this pump is a rebuilder one. Saved me a little dough.

 

[crxess]

Re: How Hard Can You Squeeze Bulb ?

To your original question.

It is possible to squeeze to hard. this will overcome the ability of the float to keep the needle sealed and will flood the carb throat with fuel.
I have a couple of motors and they will all do this.
So....only while running and the motor starting to loose power, squeezing the bulb will help diagnose a bad fuel pump or restricted supply.(trash in carb)

 

[FillupD]

Re: How Hard Can You Squeeze Bulb ?

Thanks for everyones help. My boat runs great! After I rebuilt the fuel pump and pumped it up, I noticed a very small crack in the fuel line where it exits the motor housing.
My guess is that the fuel pump was letting pressure by so I didn't see the crack. These two things together was causing my problems, or the crack was just enough to suck a little air.