5 hp Briggs Stration engine

TLD NC · Jan 24, 2015

I have a 5 hp B&S L head engine that is running rough. It has black smoke from the muffler. The choke is full open. The spark plug has black soot on it. What do you folks think the problem is? Valve problem, ignition problem, carb problem, or????

Thanks in advance for all responses.

Jo-ker · Jan 24, 2015

Sounds like your carb is dirty,take it off and clean out your fuel bowl,may have water and sediment in there....john

Kris Golden · Jan 24, 2015

If there is an adjustment on the carb it need to be turned in. Air filter could be dirty and plugged acting like a choke.

Anonymous-0 · Jan 24, 2015

Black smoke indicates too rich of fuel mixture, maybe stopped up carburetor
Soot on spark plug, could be bad plug or carb problems, or both.

Bruce Dorsi · Jan 24, 2015

Have you tried to lean the mixture by adjusting the needle valve? ...SLOWLY turn the needle valve clockwise while the engine is running at full-throttle.

Do you have a float-type carb or the diaphragm carb on tank?

If the diaphragm type, the diaphragm probably needs to be replaced and carb re-adjusted. ....If the spring is installed on the wrong side of the diaphragm the fuel mixture will be too rich.

If a float-type carb, either re-adjustment is necessary or float level is set too high. ....If the carb is leaking, the float is probably hanging open, or dirt under float needle.

ShadetreeRet · Jan 24, 2015

You didn't specify how old the engine is nor what type of equipment it is on, but judging from your description, I would try a new spark plug first, it may just be time for a new one. Then try adjusting the carburetor. Make sure there is no water or sediment in the fuel tank. If there is much fuel in the tank, you can use a battery filler bulb and suck the old fuel out and then mop it out with a rag. Make sure the air filter is clean, also. This is one of the most neglected parts on a small engine.

Duner Wi · Jan 27, 2015

If it does not have a float bowl maybe a tiny hole in the diaphragm.

5 hp Briggs Stration engine

TLD NC

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Jo-ker

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Kris Golden

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Anonymous-0

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Bruce Dorsi

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ShadetreeRet

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Duner Wi

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