Briggs 5HP push mower smokes

Bagster

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I turned my 5-HP Briggs push mower on it's side to change the blade. Now that dude smokes like a run-away locomotive. The smoke rolls out of the exhaust so thick that I can not see the grass. I mowed several minutes thinking the oil would burn off, but the plug fouled first. This morning when I went to try it again, the engine acted like it was locking up when I pulled the rope. I pulled the spark plug and the motor spun OK. Is there any fix besides tearing the engine down?
 

Rivets

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If you tipped the mower on it's side with the carb down, we have found your proble. Oil filling the card and exhaust. Can be fixed easily and cheaply. First, remove the air filter, it is probably oil soaked and choking the engine. Second, check the plug, if it is oil soaked or has a lot of carbon on it, clean with carb cleaner and a light wire brushing, reinstall. Start the engine with no air filter and let it run. (Forgot to say, "get a case of beer to appease the neighbors, as it will smoke a lot"). After the smoke clears, may take 15 minutes, install a new air filter, spark plug and top off the oil if needed. Should be good to go. Then remember, always tip with the carb UP.
 

Bagster

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If you tipped the mower on it's side with the carb down, we have found your proble. Oil filling the card and exhaust. Can be fixed easily and cheaply. First, remove the air filter, it is probably oil soaked and choking the engine. Second, check the plug, if it is oil soaked or has a lot of carbon on it, clean with carb cleaner and a light wire brushing, reinstall. Start the engine with no air filter and let it run. (Forgot to say, "get a case of beer to appease the neighbors, as it will smoke a lot"). After the smoke clears, may take 15 minutes, install a new air filter, spark plug and top off the oil if needed. Should be good to go. Then remember, always tip with the carb UP.

I tipped with the carb up. I'm thinking oil is somehow getting on top of the piston, thus causing the motor locking when trying to start with the spark plug in. Once I pull the plug, the motor spins free. During the time the engine ran and smoked, I did notice a rather disapproving look from the old boy across the street. I don't think he drinks beer, but in case he starts, I think I'll go purchase a case of Coors Light.
 

ILENGINE

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The crankcase breather assembly is behind the muffler. By tipping with the muffler down, it filled the breather with oil, then you set it back down and started, which pushed the oil over into the air cleaner and into the carb. It should clear up after a few minutes, like Rivets said. If there is a lot of oil pooling around the carb and running into the cylinder, is will cause a hydrolock situation.
 
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