Muffler Smokes

primerbulb120

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It seems that some of you are prescribing accurate methods for reducing the amount of exhaust smoke while the engine is running. My blower smokes very little while the engine is running, but smoke pours off the metal of the muffler (not out the exhaust hole) after the engine is stopped. While this could be caused by unburned oil being spit into the muffler, very little, if any, oil is spit out the exhaust port while the engine is running with no muffler.

Several facts which might be of use:

The carburetor, fuel filter, fuel lines and spark plug on this engine are all brand new.

The smoking decreases when the spark arrestor is removed.

The fuel in this engine is part of a batch that I mixed two or three days previous to running the blower. The other part of the batch was used in my weed trimmer, which runs fine without smoking at all when the engine is off.

The area on the muffler from which the smoke arises is a dull grey, while the rest of the muffler is bright and shiny.
 

exotion

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It seems that some of you are prescribing accurate methods for reducing the amount of exhaust smoke while the engine is running. My blower smokes very little while the engine is running, but smoke pours off the metal of the muffler (not out the exhaust hole) after the engine is stopped. While this could be caused by unburned oil being spit into the muffler, very little, if any, oil is spit out the exhaust port while the engine is running with no muffler.

Several facts which might be of use:

The carburetor, fuel filter, fuel lines and spark plug on this engine are all brand new.

The smoking decreases when the spark arrestor is removed.

The fuel in this engine is part of a batch that I mixed two or three days previous to running the blower. The other part of the batch was used in my weed trimmer, which runs fine without smoking at all when the engine is off.

The area on the muffler from which the smoke arises is a dull grey, while the rest of the muffler is bright and shiny.

Your two machines could require different oil mixes most higher end machines require 50:1 while lower end require 40:1 or 30:1 my poulon requires 40:1 but I use 50:1 because my echo and stihl require that and I don't want two gas cans this is why my poulon smokes same symptoms as yours I've removed spark arrestor clean air filter every few uses(it only gets used once and a while) and clean exhaust port annually I just deal with the smoke if I wanted to get rid of it I would get a seperate can and mix a proper 40:1 using a squeeze bottle that you can get at any auto part store it measures out accurately
 

primerbulb120

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Yours smokes after it has been turned off too? Mine requires 40:1 mixture, it says so on the gas cap, and that is what I put in it. You stated that you put 50:1 in your hedge trimmer that takes 40:1, wouldn't less oil ruin it? How does less oil make it smoke more? I would think that more oil would cause more smoke, not less.
 

exotion

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Yours smokes after it has been turned off too? Mine requires 40:1 mixture, it says so on the gas cap, and that is what I put in it. You stated that you put 50:1 in your hedge trimmer that takes 40:1, wouldn't less oil ruin it? How does less oil make it smoke more? I would think that more oil would cause more smoke, not less.

40:1.is 3.2 ounces per gallon 50:1 is 2.6 ounces per gallon
 

primerbulb120

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Right. 50:1 is less oil than 40:1. If you run 50:1 in a machine requiring 40:1, wouldn't it seize for lack of oil? And how would less oil make a machine smoke more?
 

exotion

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Right. 50:1 is less oil than 40:1. If you run 50:1 in a machine requiring 40:1, wouldn't it seize for lack of oil? And how would less oil make a machine smoke more?

Hmm guess I never gave that Much more thought. I've ran 3 ounces per gallon so it does get a little less oil so not sure then its just a Smokey machine
 

7394

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Possibly blow-by past the piston rings ?
 

primerbulb120

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I will perform a comprssion test on this blower. When I pull the crank, I don't fell much resistance, although I am inclined to think the problem is in the muffler, as I don't see oil coming out the exhaust when I run it with no muffler.
 

primerbulb120

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This may sound weird, but I think it's burning its muffler up. Should I get a new one?
 

exotion

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This may sound weird, but I think it's burning its muffler up. Should I get a new one?

Try cleaning it first. I usually submerge it in brake cleaner over night and then scrub what I can blow it out with air
 
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