Engine stalls at idle

Hi to all, this is my first post.

I have a 1983 Carver Mariner with twin crusader 270's(350 cu in) engines. I bought the boat in early June and live on it a Key West marina and go out on it once or twice a month. Before I moved on I had the boat pulled and a bottom job done, the engines tuned up, oil changed, fuel filters replaced, hoses replaced, cooling pumps rebuilt ect.. I trust the mechanic that did the work, I was there for most of it and he save all the parts he replaced and gave me the reciepts of the purchased items. On to the problem. Both times that I have gone out on the boat the starboard engine has given me problems. It will only start by giving it half throttle and will die when it is brought back to idle. Once it has warmed up at 1100 rpms or so I can bring it back to idle and it runs fine. I can motor out of the marina at idle without a problem. After running for 20-25 min. if I bring the throttle back to idle the engine quits. It will start right back up if I give it more gas and run great at anything above idle. As I am sure you are all aware this makes it very difficult to bring back in to the marina on one engine. I read online that it could be the coil I swapped coils and the problem still is with the starboard engine. Other than that I have not swapped out anything else.
Any help would be appriciated.

Thanks

maybe the idle ports in the carb are in need of cleaning...not that hard but most q-jet overhauls leave a lot to be desired in this area.

best thing to do is verify the problem is fuel related (eliminate the igniton) next time it occurs...it will save you a lot of aggrevation, in the long run, by actually doing the troubleshooting.

Thanks for the info. I was sort of thinking it was carb related. The carbs are after market ebelbrock is that the same as q-jet? What is the best method of cleaning the idle ports? I was thinking of using seafoam in the gas or is that a waste of time and money?

Classic slow flooding. Need to rebuild the carb.

Jeff

edelbrocks are not the same as the stock Q-Jets...that means your carbs have been replaced.

The best way is to remove the carb, disassemble it, and soak it.