Westerbeke Generator.

Wasnt sure where to put this but I was hoping I could get some ideas about whats going on. Our boat has a 12.5KW BTG Westerbeke Generator. This spring it was very hard to start and smoked pretty bad. Under load it simply died. We traced it down to something thats called a accelerator pump diaphragm. This engine uses vacuum to squirt gas into the carb when the throttle opens. Anyway, the bad diaphragm was allowing gas to get sucked right into the intake manifold thus flooding it. We replaced that and it started and idled great. When we placed a load on it it would still die. We then figured out if we kept the choke ~1/2 closed we could load the generator up 100% and everything was ok, it seemed to struggle more than normally(the choke was closed after all) but it got us through the weekend. So right now Im thinking the engine still isnt getting enough gas since it runs 'ok' with the choke partially closed. Weve checked the fuel pump and its pumping ~3psi. We also broke the carb down and checked it out. Not sure what it was but it had a lot of very fine powder in the bottom of it. We sprayed carb cleaner through all of the jets and they appear to be clear. Also cleaned out the screen/fuel filter. So this is where we stand, runs ok with the choke partially closed, spark plugs are new although Im going to check them to see what they look like. The thing likes to back fire through the carb when the choke is wide open, but from what I could tell its not getting any gas out of the accelerator pump when its running and I move the throttle. Vacuum is ~15psi right off the manifold. Going to check the RPM(it runs at 1800 rpm idle) and timing as soon as I can.

Heres a break down of the carb just so you can see it. The accelerator pump is on the bottom right. A rebuild kit is $70 for this little single barrel carb so were trying to stay away from that. All it comes with is a needle valve+seat, and some gaskets. Its pretty useless for $70.

Re: Westerbeke Generator.

Sorta confused why this got moved to a forum that clearly says 'NOT ENGINE TOPICS.' Doesnt matter to me either way. Anyone want to take a stab at whats going on?