2009 Mercrusier 3.0 2 barrel TKS carb Gen 2 flooding at idle (intermittent)

[rcer22]

Hey folks
I was following another topic with a similar problem and it has stopped and I assume not been resolved.
My problem is an intermittent one. I have flooding above the throttle plates at idle. I have done the carb over and checked and even lowered the float level. I even changed the float itself thinking that it might have been heavy. I put the carb back on and it ran great for about a week. Now the problem has returned. I see no fuel in the yellow tube coming from the fuel pump. Is it possible that running the high octane non ethanol fuel could be causing the problem? I know the engine can run on 87 octane but it contains ethanol and the high grade stuff supposedly does not. It is sitting at the marina right now waiting to be looked at. I think they're going to want to just rebuild the carb and figure that will solve the problem. However I think there is something else going on and I'm going to get stuck out on the water. I don't have a lot of faith in the mechanics there because one them told me I don't have an adjustable mixture screw. I had to show the guy that I did one and where it was. The alternative is to take the boat out of the water and bring it somewhere else. Royal pain doing it by myself. I also am quite sure when I do get the boat somewhere else the problem wont happen. It only seems to happen when there is no one to show it to. Like on a Sunday afternoon when all the worker are gone. Then the next day it's like it never happened. I'm out of ideas as to what's causing the flooding. I haven't looked at anything electrical because I just cant see this problem as being anything other than a fuel related problem. (High fuel pump pressure) maybe although my car experience has taught me that when a fuel pump fails it delivers little or no fuel at all.
Any thoughts are welcome.

 

[Fun Times]

Being you see it above the plates, one thought would be the needle and seat may be bad. If the carb comes back apart, may as well try a new needle and seat kit just to be sure.

Page 5B-10 should help give you some ideas to consider. http://boatinfo.no/lib/mercruiser/manuals/mercruiser41.html#/42

Have you check and replace spark plugs since it has been running rich?

Let us know what you or they find, good luck.

 

[rcer22]

Thank you for posting that link. I do have that and I have already printed it out and in a book. I found that 3 years ago probably from one of these forums.
"Have you check and replace spark plugs since it has been running rich?"
No I haven't even looked at them. The way I see it there is no point in changing them until the flooding is fixed. When the engine is running it runs very well with no missing or backfiring. In fact until it does it flooding thing you would never know there was a problem. It runs beautifully. It will idle all day if you let it. (In drive!)