1991 1800 SR is loading up and flooding

[Cmattingly]

Hi all First boat and it seems to be flooding and taking on way too much fuel. This is my first boat and it is has been frustrating. Any suggestions on possible causes for the flooding?

[mmwjr]

Welcome aboard

Is this occurring while under way, idling, or when shutting the engine off?

What engine and carb do you have?

[Cmattingly]

Both while idling and underway! We took the air filter off and could see gas in just sitting after she dies! Should it be idling at 500 rpms? I am very new to this and any help is greatly appreciated.

[mmwjr]

Still do not know which engine you have but I suspect the idle should be between 550 and 650.

Sould like the carb needs a total rebuild, not uncommon for its age.

[deanries]

The 3.0L Merc has a MerCarb carburetor that was known for this problem so they came up with a spring in the float needle. Had the same issue with my 92 shortly after purchase (bought new). The engine should idle in the 800 -900 rpm range in neutral which should put the idle at 600 rpm in gear. A lot of info online about the MerCarb and this problem. Hope this helps. Looking forward to another year on the water!
Dean (Go Big or Go Home)

[Dysfunctional]

How would you check for this. I have a 1991 1800sr with 3.0L mercruiser that I only bought..

[deanries]

The 91 1800SR with the 3.0L engine should have the same 2 brl MerCarb that I have on my 92 model. I have found that Nikki built those carb's for Mercury Marine so specs & re-build kits are available. You will need your engine serial number to get the proper kit, mine was OD803211 which has a 1389-9562A1 MerCarb carburetor. My rebuild was successful and now I am ready for the water. If you enter Mercruiser Carb Rebuild in your search engine on your computer (Google or others) you will find help for your issue. Good luck and let me know the results!
Thanks, Dean