Hey all. A while back, at the end of last summer, I had my boat worked on because we were stranded in the lake 3 times with a motor that just quit while running and would not restart.
After having the motor fixed, it has run fine, but the other day, while off shore, she stalled again and died for about a half hour.
When I took the cover off, I noticed something I had not seen before. The fuel filter had air in it. The top eighth or so was air and the bulb on the fuel line was very soft. If we turned her over while squeezing the bulb, we could get it to run a bit. During this time of experimenting, we saw that this process got rid of the air, the bulb went stiff again, and the motor started back up.
So, my question is, how can I be getting air into my system? And, would this have anything to do with it stalling out, or are these two not related? Thanks.
I had a very similar problem a week ago. Air would build up in my filter and the engine would stumble then quit. Priming would get it going again for 15-20 mins.
Any line between the tank and primer is suction. You can have a leak and not see it. It will suck air causing your issue. I plugged the line at my tank and used a little puff of compressed air to put back pressure on my suction line. I found a bad clamp that felt tight when turning but it was not. If it was after your primer bulb you would see it when you prime the system.
So no one has any suggestions about this for me? Is is normal to see an air pocket at the top of the fuel filter? It seems like once we forced it out is when the motor ran again and we got pressure in the bulb on the line.
I think MattR has it - I had a similar issue for a while. Ran fine, but sometimes very hard to get restarted, and it would take forever to prime the system.
I replaced the fuel line & hose clamps from tank to motor, including primer bulb and problem went away. I suspect there was a small air leak on the suction side somewhere, in my case the most likely suspect was the fuel tank outlet barb - it was corroded as heck and fuel line where it connected was in bad shape.
Even in a perfect system it could take a few tries to chase all the air bubbles out if the line was dry to start, but as I understand it once it’s primed it should pretty much stay that way, and should be solid gas from tank to motor with no air pockets. If the bulb goes soft, it’s because the gas that was in went somewhere. If the motor is running more is going out than is being pulled in, and if motor is off it either leaked out or drained back to the tank, neither of which can happen unless air can get in to displace the gas. The check valve in the bulb will limit backflow somewhat, but the ball won’t seat tightly unless its under pressure (as in when bulb is squeezed) and regardless won’t prevent the rest of the line from draining back to the tank.
I guess it could be a cracked hose, but more likely a connection somewhere. Have you tried replacing the primer bulb? check every connection to make sure the rubber is in good shape and clamp is tight, including the seating surface for all filters. Or if you want to be sure replace everything. Cost me about $50 for bulb, line, and clamps, and problem solved. Good luck!
Hey all. A while back, at the end of last summer, I had my boat worked on because we were stranded in the lake 3 times with a motor that just quit while running and would not restart.
After having the motor fixed, it has run fine, but the other day, while off shore, she stalled again and died for about a half hour.
When I took the cover off, I noticed something I had not seen before. The fuel filter had air in it. The top eighth or so was air and the bulb on the fuel line was very soft. If we turned her over while squeezing the bulb, we could get it to run a bit. During this time of experimenting, we saw that this process got rid of the air, the bulb went stiff again, and the motor started back up.
So, my question is, how can I be getting air into my system? And, would this have anything to do with it stalling out, or are these two not related? Thanks.
I had a similar problem with mmy Johnson system. The connector at the tank will open a tank valve to allow fuel to flow. If the throw on the tab that sticks out of the tank connector is not depressed sufficiently or consistently it will not allow fuel to flow and the connector may allow the fuel pump to suck air in the connector or any small leak in the suction side of the bulb. The fuel pump will suck to collapse the bulb and make it soft or flat. Just the movement of the fuel line may be enough to make the valve work and cause an unknown temporary solution. If there is a hose leak on the pressure side of the bulb, there will be a detectable fuel leak. Hope you find the problem.________________________________________________
