I recently have been trying to get my used /new boat to me running- I got the boat to idle in my driveway a few times and and have narrowed my diagnostics down to the fuel delivery sytem. I changed the fuel filter in the carb- new water fuel seperator - new gas -treated the gas with startron. and used a little gumout a nd startewr fluid only to have the negine conk out when I gave her a little throtttle--- Well i believe my prob has been the carb -the guy before me painted the carb body so i had to chip off the paint to see the numbers well the numbers did not match the what the mercruiser serial engine tag read so im pretty sure that its a areplacement carb and believe the guy sold the bolt because he coulodnt get the carb situation under control-anyway -the carb is suppose to be a mercarb 3310-807504a1 or 3310-805924a2 and lastly 3310-864940a03 I found the first one online for a ridiculous 630 dollars. Iknow that sierra makes some replacements but i cant figure out which would be suitable -can anyone shed some light on this -My last choice would be to rebuild the one thats on right now -thanks again for any input. Ill post the carb numbers on the one thats on the engine now -i have to run out and get them-maybe someone will be able to tell me what carb it is. 861245 followed by 8602 its a a 2 barrel but i dont what make it is.