Yamaha 150 not getting gas???

[Blue Water 23]

I have a 2004 21 ft. North River Seahawk with a T-8 and a Yamaha Four Stroke 150. The T-8 has been running fine all day. The 150 is not getting fuel. I pump the ball to prime it and it runs fine for a while, then it quits getting gas and runs rough and eventually dies. The ball goes limp shortly after the engine is started and the ball isn't pumped. It takes a lot of pumping to get gas thru like the line is empty.



If I pump the primer ball while running it runs fine for long periods of time. It runs from 20 seconds to a couple minutes after I stop pumping the ball but runs good again after pumping the ball. The kicker and main both run off the same fuel line/tank.

Lots of good gas in the tank. (The kicker runs good and the 150 runs good when you pump the ball). When the ball is pumped a lot there is a little gas slick behind our boat at idle.

Fuel pump problem?
Injector stuck open?
Leak letting air in?

What do you experts think? Anyone else experience this problem? Thanks for the help!

[smalldog]

filters or pumps.

[MattPark]

Tighten all fuel system lines to the main, and swap the primer bulbs between the motor. An air leak or bad primer bulb could be your problem.

Could also be a VST or injector issue. Here's a good writeup with pictures on how to change the VST (you can also clean it as opposed to replace it). It's not a terribly uncommon problem, and not as difficult as it looks in the pics.

A fuel pressure gauge is a good tool to have when diagnosing an EFI engine. It connects directly to the fuel rail, and you can monitor pressure when the issue is occuring. If pressure isn't dropping, you know it's not fuel related, at least up to the injectors. My guess is your pressure is dropping for some reason.

The injectors and screens can become clogged as well. They are super simple to pull, and fairly straightforward to clean, but I think your problem lies in the supply to the engine. If you aren't running a 10 micron fuel water separator, I'd change that over. Fuel injected engines are a lot more sensitive than carbureted when it comes to tiny particles in the fuel.

[smalldog]

It is the U shaped filter on these that usually clogs.

[No Reservations]

Sounds alot like a problem a friend of mine was having turned out to be water collecting in his fuel injection rails his t8 ran fine not as sensative to bad fuel like stated above he said it was very easy to remove them and blow them out with a compressor.

[goatram]

My 04 Seahawk's t-8 fuel bulb died this last weekend. the F150 Died last spring. If it is the original one Replace it. New one costs $11. Your back in the game. While your at it check the filters like the others have said.