99' Johnson 150, air in fuel system?

[MikePags]

Hi, my first post,, please help me. I have a 99 Seaswirl Striper CC with a 99 Johnson 150 Ocean Pro. Here's the prob: I can start cold priming the bulb, and can literaly run flawlessly at 4k RPM for miles. My problem is when I go to restart after shutting down. I have to re-prime the bulb again as there is none to little fuel in the line and mostly air. Sometimes the motor runs crappy for a few minutes afterwards until the air is gone. Here is what I have done so far.
1. Replaced the primer bulb 2 times with new, one is a Yamaha.
2. Eliminated the ball check valve at the fuel tank.
3. Checked all fuel lines and vent line for leaks and or clogs.
I suspect something at the motor, fuel pump or some diaphram thingy that is letting air into the system. Any trouble shooting ideas, and diagrams of the fuel system that would point to where I might start taking things apart for diagnosis. Thanks so much. Mike

 

[reload]

Re: 99' Johnson 150, air in fuel system?

Why did you eliminate the ball check at the tank? This will allow more siphon pressure on system. You have to be sucking air somewhere. I would suspect the lines or pump, could be connection points anywhere along the way.

 

[WillyBWright]

Re: 99' Johnson 150, air in fuel system?

Put the antisyphon valve back in. It's a check valve that should prevent fuel in the line from running back into the tank if it's working properly. Check all of your hose connections between the tank and fuel pump. Don't use metal screw-band clamps on any plastic fittings. If you have any, take them off, cut off the portion of hose on the fitting, and refit and clamp with plastic clamps. You can get special zip-ties that are made to clamp hoses, and there are SNP plastic clamps that work very nicely. The problem with the screw/band clamps is that they warp the plastic fittings and sometimes restrict them. All of your fuel line should be 3/8" diameter.

 

[MikePags]

Re: 99' Johnson 150, air in fuel system?

Thanks for the reply's folks. I'll replace the anti-siphon valve as it didn't change or fix my problem anyway. I was just wondering if there was a way of pressurising the system, like trouble shooting a cooling sys in your car. I won't try that unless I hear from a mechanic on how, for the fear of making something worse. I'm gonna go re-fill my coffee now and go look some more for leaks.

 

[reload]

Re: 99' Johnson 150, air in fuel system?

I'm sure you can rig something up to pressurize the hose, just be careful not to use to much pressure. How long is the fuel line?

 

[Johnalcon]

Re: 99' Johnson 150, air in fuel system?

My 2001 150 Johnson was doing the same as yours. I had to repump the bulb after after a brief shutdown and rev it up a bit to keep it from dying. My fuel filter plastic nut was a bit loose and must have been letting some air in. Once tightened, the problem was gone.