Fuel Primer Bulb Collapsing

[albernifisher]

I had the exact same thing happen to me two years ago in Bamfield after I got ****** gas. Thought the anti siphon valve in the top of the tank was plugged so IIok it out,wasn't the problem.The problem was the filter in the raycor was plugged, ran fine at idle and slow speed but when I opened it up the filter wouldn't let enough fuel through and the suction would crush the ball.I run a diesel filter on my ray or which is a lot finer then a gas one so it plugs a lot quicker

 

[Finished Business]

maintenance update....

I was at the boat yesterday and decided to try the first set of options listed to try and figure out this fuel issue. I started with righting the primer bulb to a straight vertical position. With the hatch open so I could see the bulb under power, I went WOT down river for a few miles. Longer than I had run the engine to date WOT. No problems!
The bulb stayed firm and fuel of fuel. There was no reduction or collapse in the bulbs size.

Now I am not ready to say "Yup, its fixed", but it was a promising trial. Another thing I noticed is prior to my trial run, I pumped the bulb in its original horizontal position. It will move fuel but would never get hard. Similar to what I read online through various forums. Most of the forums followed up with the user righting his bulb to vertical, and immediately after making the modification, a few pumps and the bulb would stiffen right up.
Sure enough, the exact same scenario happened to me. As soon as I put the bulb vertical, four squeezes of the priming bulb and it became very hard and pressurized. A complete 180 from the horizontal position.
I am near confident though it is not a breather issue. As mentioned, the fuel line is 3/8" diameter. My breather is actually has a inside diameter of about 5/8", so nearly twice that of my fuel line, No matter how much fuel is drawn, I don't think it is possible to create a vacuum as a result of the breather line.

I still think it could be an obstruction issue in the tank, but if I go out another 2-3 times and really pump some gas through at WOT with no problems, I think it can be attributed to the position of the priming bulb.

Thanks for the insights guys. I will keep you posted on further developments. I would recommend to everyone, check the position of your primer bulb. It is likely a very very easy mod (took cutting one zap strap and relocating it for me) and it will certainly not hurt, even if you are running horizontal without issue.

I should note: position the bulb vertical with the fuel flowing skyward.

 

[CIVANO]

If you remove the antisiphon valve from the pickup, make sure all fuel lines are zip tied higher than the highest level of fuel in the tank. If they are lower and you get even the smallest leak, the leak will siphon all gas above its level into the bilge.

 

[Finished Business]

I won't be going into the tank this season. But you make a great point regardless. During my build I was working on the fuel lines (with minimal fuel in the tank) and i set a line into the bilge as I was zap strapping from the tank back. I went to grab a tool or beer, and the line that i had laid in the bilge started to siphon what little fuel was in the tank. I never considered something so simple as keeping the lines above the tank (it worked out in the end that I did anyways) but its the little things thank can make all the difference sometimes.

 

[staying alive]

I was out getting some spare parts to keep on board the other day and bought a spare merc primer bulb and read the instructions was surprised to read about keeping it vertical when priming, who new you where supposed to read the instructions.Now my kicker runs better, are you supposed to leave it in the upright position all the time???
S

 

[Finished Business]

ideally yes. I will be at the boat lots this weekend and will run some more fuel through and see if it remains stable. I will be trying the adjustment on my kicker as well. I like free repairs that make all the difference!