I have a Craftsman 6000w generator with an 11hp Briggs with Nikki carburator.
Runs rough and black, sooty smoke in exaust. I've pulled and cleaned the carburator and pulled the cylinder head. Head is sooty. A small rubber cylinder with a groove fell out of the carb when I was taking it apart and I'm not sure where it goes. It's called a slow flow plug. The engine acts as if it's flooding all the time but I have tried everything I know to do. Cleaned the carb twice to no avail. Only one adjustment screw on top of the carburator and it doesn't seem to make any difference whatsoever when changed. Thanks.

For one, check the oil level. If it was flooding, the oil level can increase with raw gas. So, you may have to change the oil.

Cleaning the carb may require disassembly and sometimes a rebuild kit.

Just in the gas tan, like rust, is notorious for keeping the fuel valve open.

Your probably also going to have to put some carb cleaner down the spark plug hole and have the engine spit it all out in a rag.

Also don't ever use starting fluid for a small engine. Carb cleaner is much better because it contains lubercation.

Go to Parts & Accessories | Shop & Find Lawn & Garden, Appliance Parts at Sears Parts Direct | SearsPartsDirect.com from Sears and look up your model of generator. There should be an exploded view. It may take two tries to get there. One to get the engine # and then use that to get the breakdown of the engine. Then you can figure out where your piece goes.

Thanks for the quick response. I completely dissasembled the carburator to clean it when I took it off. One of my problems is not knowing where the rubber plug goes that I mentioned in my first posting. Oh yes, I did use GUNK carburator cleaner. I will try some in the plug hole once I get the head back on. Everything looked good under the cylinder head however, except for the soot. Gas tank is not metal. I will check the oil level.

Ooops! I didn't see the last part of your answer on looking up the exploded parts on the carburator. I've done that. The view shows the plug but does not show where it goes. It's a separate view off to one side. I don't think it's this plug causing the problem however. The engine was missing prior to tearing apart the carb. I'm still mystified as to what can be causing the poor performance. Thanks for any help, it's appreciated.

Check Home - Briggs & Stratton for a better blowup and parts list for the engine. The carb should be shown separately.

After more research, here is what I have. The engine is a generac EHF-00945-1 with a 410HS carburetor even though the manual from Sears says it's a Briggs. I have tried all the obvious places for info and still no help. Even the folks at Generac were no help. I can find the slow flow piece on an exploded drawing but not where it goes. Any help?

I found the carb here: Generac Parts - 0A45310194 thru 0A5925 and what looks like the service kit.

You might be able to get some help there.

What's the sears model number? Many parts diagrams are located at Parts & Accessories | Shop & Find Lawn & Garden, Appliance Parts at Sears Parts Direct | SearsPartsDirect.com from Sears so I can look there.

Thanks for the info. The Sears model is 580.327160 serial # 5394015