Pimer bulb collapses

[DennisM1358]

We have a 16? cc with a 2000 50hp Johnson. The motor was running great so to keep it running great I decided to replace all the fuel lines and primer bulb from the outlet on the splash well to the motor.

We put the boat in the water this morning and the primer bulb pumped right up and the motor cranked right over. After running for several minutes the bulb collapsed but the motor kept running? We ran the motor for about 30 min at all different speeds and it ran great?

Back at the dock I disconnected the fuel line from the water fuel separator and ran it straight to a portable tank and the bulb stayed nice and firm so I am figuring that there is some kind of blockage in the pick-up tube.

I have a portable 12 volt air pump that is used for car and bike tires. I was thinking about using the pump to blow air from the fuel supple line nipple at the splash well to clear the blockage?

 

[Bt Doctur]

Re: Pimer bulb collapses

Ever think the water/sep might be plugged up?

 

[DennisM1358]

Re: Pimer bulb collapses

The water fuel seperator has a new filter and while I had the fuel like disconnected from the nipple on the splash well I blew air through the hose and it was not restricted?

 

[Vlad D Impeller]

Re: Pimer bulb collapses

clog in seperator or air leak in fuel line

 

[steelespike]

Re: Pimer bulb collapses

If you have a built in tank perhaps a mud duaber built a nest in the vent.

 

[DennisM1358]

Re: Pimer bulb collapses

all the fuel line connections are tight. I ruled out the fuel pump since it ran off the portable tank and the primer bulb stayed firm? I thought when a primer bulb collapsed it was due to a restriction from the primer bulb back to the tank pick-up and since the primer bulb stayed firm when used with the portable tank that ruled out the primer bulb?

 

[coolguy147]

Re: Pimer bulb collapses

open the vent?

 

[DennisM1358]

Re: Pimer bulb collapses

I also thought the vent could be clogged so I opened the fuel cap while the motor was at idle and the primer bulb was still collapsed?

 

[capt sam]

Re: Pimer bulb collapses

anti-siphon may be partially stuck closed, it's drawing a vacuum so it's not an airleak and you have no issues on a portable tank.

 

[DennisM1358]

Re: Pimer bulb collapses

I was thinking its either the anti syphon valve or a clog in the pick-up tube. Is that something I can clear up by blowing compressed air back down the fuel line or does it have to be removed from the tank?

 

[capt sam]

Re: Pimer bulb collapses

I have cleared the pick up with a nozzle off a compressor. I would go ahead and pull the anti-siphon out and get rid of the spring and ball and reinstall it, those things cause way too many problems.

 

[joho5]

Re: Pimer bulb collapses

might sound silly, but make sure your fuel line from your tank to the motor isnt backwards...

 

[DennisM1358]

Re: Pimer bulb collapses

The problem has been solved, Thanks for everyone?s input!!

It ended up being a two part problem centering on the new quicksilver primer bulb. The quicksilver primer bulb is made of very soft thin plastic and the way it was lying in the splash well was restricting the flow a little and since the plastic is so thin and soft the vacuum from the fuel pump collapsed the ball. A new stiffer primer ball was installed this morning and everything worked as it should.

 

[bowman316]

Re: Pimer bulb collapses

i have had my bulb suck together before, like when you suck your cheeks together. And i disconected it from the motor, and put it right back on, and when i put it back on, i heard air rush in the line, and make the primer bulb plump back up.