so I have an old Renault 4 cylinder inboard boat engine here. it's older than I am and has a carburettor which you initially fill with gas by pumping it manually from an external tank using one of those squeezable valves. I can get it started but I can't keep seem to keep it going. I have to fiddle a bit with the choke while pushing the ignition but it does start and then it runs for a while really loud . I have to keep squeezing in gas to keep it alive but eventually even with that it cuts out. it seems that the loudness of the engine is very sensitive to the throttle, the choke and the gas squeezer, so I suspect that it's something to do with the fuel system but I don't really know . anyone have an idea what might be going on here?