fuel problem

[robbie lee]

hhi can u help . i have 2x 5.7 volvo petrol engine she runs very lumpy on idle and pops and bangs when revs r picked up .when removed carbs inlet mainfold is dripping in fuel carbs about 10 years old but why both engines . on tick over just leaves lot of film of fuel in water and very heavey on fuel cheers yo yo

[matt h]

choke permenantly open, dirt in needle housing causing severe rich mixture, likely cause is where the fuel pipe enters the carb housing, there is a small ball valve, to stop excess fuel going in to the bowl, sounds like the chrome ball is jammed open letting a constant flow of fuel in to the bowl,and not shutting off, its happened to both probally because there is moisture in the ball valve and that has caused corrosion, need to take the tops of the carbs off and check that they are closing and opening freely,

[antiqueboy]

had a similar problem on an out board.
the air intakes leaked fuel and engine ran awful.

the ball valves stuck open caused by dirt

cure for my outboard was disconnect the fuel when the engine is running, but keep the revs up, and high just as she runs out of fuel.
the engine trying to stay alive by sucking in more air, and removes/removed my block

top tip from by local service engineer, hope it helps you.

nick

[Nos4r2]

Originally Posted by robbie lee

hhi can u help . i have 2x 5.7 volvo petrol engine she runs very lumpy on idle and pops and bangs when revs r picked up .when removed carbs inlet mainfold is dripping in fuel carbs about 10 years old but why both engines . on tick over just leaves lot of film of fuel in water and very heavey on fuel cheers yo yo

Before we all diagnose this I think there's more information needed.

Are you using single/twin tanks?
Did this occur suddenly while in use, build up slowly or appear after a period of not being used?
What's the linkage to your chokes? Auto,solenoid or cable?
Do you have a water trap fitted and does your tank filler seal properly?