96 Johnson 150 fuel delivery issues

[qwest]

Hi,

Im working on a 96 johnson 150 ocean runner on a 96 hydra sport 1900. Motor runs fine on external tank, but put gas in boat tank today and had trouble getting fuel to it.

I can't seem to get the right amount of fuel from the tank when I pump the ball on the fuel line and ive tried 3 different lines. it pumps very little gas has trouble filling back up almost like it is getting choked out. water separator is filled to the top and there's plenty of gas in the tank.

Anything will help. thanks

 

[tphoyt]

How old was the gas that was already in the tank and when was the last time the filter was changed in the fuel water separator?

 

[Chris1956]

Check the fuel tank vent and the anti siphon valve in the fuel pickup tube.

Some fuel tank pickup tubes have a filter that can clog.
The A-S valves can clog.
Fuel tank vents can clog as well.

Were you using the water separator with the external tank? If not that needs to be checked for clogs or replaced. Some choke off the fuel supply if they fill with water.

 

[qwest]

Thank you for the insight. the gas in the tank is new as of yesterday. I did what I could to drain as much old gas out as possible. The water separator isn't new, but I have detached it and refilled it with new gas, I will pick up a new one today.

I will check for a clog in the vent , but I did try to open up the actual cap for the tank to vent it out and that didn't work, not sure if that would make a difference.

where is the anti siphon valve?

 

[Chris1956]

The Antisiphon valve is somewhere on the fuel pickup tube. Most screw into the elbow of the pickup. They look like aluminum or brass hose barbs, but have a spring and ball inside to effect the valve operation.

Some A-S valves are located in the fuel pickup tube itself, as sometimes filters are. So if the fuel is restricted by the fuel pickup tube, it is best to remove it and see what is causing the restriction.

 

[qwest]

Did some more work today.
the fuel line connections go gas tank-> port side water separator -> starboard side ball pump-> motor (4 hoses)

I inspected every hose and couldn't find anything. I then disconnected the hose from the actual tank and put the ball pump hose on the tank itself and still nothing. Still seemed choked out. I then disconnected the actual pickup tube from the tank to inspect it and its clean, no clogs, clean filter. I even attached the hose with the ball pump directly from the tank to the motor and tried to crank and it still does not pump gas. All of this with the vent hose disconnected and free from a clog in the brass barb connection to the hull of the boat

then I put the pickup tube in a small tank full of gas and it still seemed like it was choking out. I find it unlikely that both ball pumps would fail, and that is the original (clean) pickup tube for the boat so I don't understand why it wouldn't work. I can provide pictures if need be.

Should I just buy new Pickup tube and ASV?

 

[Chris1956]

If you can see clear thru the fuel pickup tube, I am not sure what to suggest.

Alternatively, sometimes the fuel pickup tubes unscrew from the elbow fitting, and there is a filter under the tube. Have you located the antisiphon valve? If not, that would be a good idea. They can clog.