Stalling upon acceleration

[dachshund23]

1990 Stingray Mercuiser 6

Engine has been stalling intermittently. Changed fuel filter and separator.
Put Sea Foam in gas tank. At first it stalled upon start up. Now it is running at idle (45 minutes) even full idle when asked. Runs at wake speed with few stalls. When asked to accelerate past wake speed feels like it wants to go, but gives a puff and stalls. Does anyone know what I can do to fix it? Any help would be appreciated. Novice at engines and boating.
Amy

[gonzo]

Sounds like the carburetor needs to be rebuilt.

[dachshund23]

Thanks for the quick reply. Rebuilt? That is a bummer. Do you know what would cause it to need that?

[gonzo]

Old gas forms deposits. Also, as the gas evaporates it leaves behind the heavier compounds, that is tar and asphalt.

[dachshund23]

Thanks for the info Gonzo!! I guess there is nothing I can try in the meantime to try to fix it easily....and cheaply. Have a good weekend!

[bcalhoun]

I had some of the same problem. I adjusted the air screw and seemed to help. Do you know the proper adjustment on the screw? Besides Carbon build up, what would cause it to keep running after shutting it down, like dieseling.

[dachshund23]

Thanks for the note. Yes, my mechanic came down and took the carb and I think cleaned it. He said to run the boat and let him know next week. I accelerated it to plane twice, each time I cut back on the throttle to try to get it to stall. Did not stall until the third time. I adjusted some screws last weekend, now maybe I need to adjust them back. I will check that air screw. Is that the screw that is the vent for the gas tank? Thanks for the help. I can use all the advise I can get!! Have a good weekend bcalhoun!

[dachshund23]

I tightened the fittings and still stalling. Anyone know what to do? Very much appreciated!!!