Carburetor Help

Last summer I had a gas leak out of the carb onto the top of the intake. I took my boat in to the repair shop for something else and they noticed it. Said it was a serious fire hazard and I quickly agreed. I agreed to let them take a look at it. They said it needed "rebuilt". It was running perfect, though it was pretty good, so for about $175.00 I agreed to it. They got it done and I put it back on the water. It started once and ran pretty good, about like before the rebuild, then wouldn't start again. I pulled the air filter cover and saw that it was just pouring fuel in. I took it back to the shop again and they "fixed" it. Now it is hard to start, idles about 75% of the time and doesn't accelerate like it used to. I know that most of you think I should take it back and make him fix it but that is out of the question. The work was so poor the last time that I would be well ahead if I just take care of it without him knowing.
So now to the question...
My boat is a 1990 Supra Sunsport with the 351w motor in it. I am looking at a new carb on discount inboard marine. I am pretty convinced that i am going to put a new carb on and hopefully call it done. My question is how tough is it to get the new carb adjusted correctly and ready to roll. I talked to Discount and they told me that it is pretty well adjusted out of the box. I have just heard horror stories and don't mind too much to pay someone to do this work if I really need to.
Let me know and thanks for all the help.

Where is it leaking? Could be a stuck float, but that should have been fixed with a rebuild. My next thought was possibly a ruptured fuel pump, that's designed to dump into the carb instead of the bildge, and wouldn't be fixed in a rebuild.

As far as the new carbs go, everything that you might need to do is on the Holley website with YouTube vids. It's all pretty straight forward, it should run right out of the box so just a bit of fine tuning would be the most you would have to do.

personally I would go back and get the shop to fix it right---third times the charm. $400 more for a new carb and you may have to pay someone else to dial it in. Ski Dim does know those 351's and you may be able to bolt it on and go...but it may need some adjustment too.

I rebuilt the carb on my 89 Supra a few years ago there is a lot of little things that can go wrong if your not careful.
The two things that cause that on a Holley is floats and power valve .They did you right to just rebuild it as its not worth trying to fix them without a rebuild on an old carb . Did the shop drive the boat after the repair? I would take it back and insist the put their best man on it and make it right or refund the money . A new carb will probably fix it they are very easy to install and adjust but they are pretty expensive . If you are anywhere near Lake Lanier GA let me know I will help you with it for free.

I really appreciate the help guys. Thanks for the input and offer to help Michael. As I said before the place that worked on it originally will not see the boat again. I can get a pretty good deal through work on the new carb so that is the way that I am going to head. I just wanna have a pretty reliable boat on the water this summer and the old repair shop isn't going to give me that. Thanks guys.

It sounds to me like they didn't adjust the carb after it was rebuilt. Did they even run the boat after they worked on it?