Smokey

Mike wolland

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My 20 hp single cylinder B&S MOTOR starts out running smooth then the rpm drops and it starts smoking, bad!!
Cleaned fuel tank and lines, cleaned spark plug and it runs smoother but still starts smoking.
Any ideas??
 

bertsmobile1

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White smoke is oil
Remove the air filter and see if it feels oily
A blown head gasket can over pressurise the crank case which causes oil mist to be blown out the breather tube & into the engine
A bad breather valve can have the same effect
Too high oil level also does the same thing .
 

Mike wolland

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Blown head ga

White smoke is oil
Remove the air filter and see if it feels oily
A blown head gasket can over pressurise the crank case which causes oil mist to be blown out the breather tube & into the engine
A bad breather valve can have the same effect
Too high oil level also does the same thing .
Air filter is oil free and oil level is normal. Will check breather.
 

Mike wolland

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Thanks for your input everyone!
Will be putting in a new head gasket today. Looks to be blown at the valve side
 

slomo

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I thought white smoke was anti-freeze/water? Blue smoke was oil? Black smoke is from excessive fuel?

Make sure you lap the head and block gasket area flat. Every small engine head I've removed had some level of warpage. Torque the bolts to factory spec.
 
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