Oil coming out of muffler

Reinman

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I found a Briggs and Stratton 10T802-3776B1 on the side of the road. When I went to drain the oil, I tipped carb/air filter up to drain through the dipstick and oil was pouring out of the exhaust. I thought I had the cylinder at TDC. Any ideas of why this could occur - something internal? If I didn't have it at TDC, would oil pour (not drip) through the exhaust? Trying to figure out is this little guy is worth saving.
 

slomo

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Couple things.

Oil might be over full as in ridiculous.

Carb needle and seat might of filled the oil sump with fuel looking like an over filled oil sump. Smell the oil for fuel.

Go ahead and dump all the oil out. Some engines have a bottom oil drain plug where the blade is at.

Return mower upright. Let it set for say 10 minutes. Turn it over and dump any remaining oil again.

If the oil smells like fuel, you need to clean/rebuild the carb. Don't get on ebay or amazon and get a Chi'sneeze cheapo carb. Clean or rebuild the OEM carb.

slomo
 

Born2Mow

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I think you were at TDC.... on the Exhaust stroke. The piston has a hole in it, and so the oil came through the piston and out the Ex valve, which is open on that stroke.
 

Reinman

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I think you were at TDC.... on the Exhaust stroke. The piston has a hole in it, and so the oil came through the piston and out the Ex valve, which is open on that stroke.
Both valves were closed which is why I’m so puzzled. How does oil pour - not drip through the muffler when tipped on its side?
 

Reinman

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Couple things.

Oil might be over full as in ridiculous.

Carb needle and seat might of filled the oil sump with fuel looking like an over filled oil sump. Smell the oil for fuel.

Go ahead and dump all the oil out. Some engines have a bottom oil drain plug where the blade is at.

Return mower upright. Let it set for say 10 minutes. Turn it over and dump any remaining oil again.

If the oil smells like fuel, you need to clean/rebuild the carb. Don't get on ebay or amazon and get a Chi'sneeze cheapo carb. Clean or rebuild the OEM carb.

slomo
I think it was overfilled - a lot of oil came out. There was water in the gas tank - totally cleaning the carb and replacing the gasket. Oil also came through the breather onto the air filter. I guess I can’t drain this one through the dipstick like I’ve done with other mowers. First time I’ve seen oil come out the exhaust and breather when tipped.
 

slomo

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I think it was overfilled - a lot of oil came out. There was water in the gas tank - totally cleaning the carb and replacing the gasket. Oil also came through the breather onto the air filter. I guess I can’t drain this one through the dipstick like I’ve done with other mowers. First time I’ve seen oil come out the exhaust and breather when tipped.
OIl will move where it's not supposed to be at on an over fill condition. Things like poor sealing valves, auto compression release and such. Just get it all out. Put some SAE30 back inside exactly at the FULL mark. Not over not under. Check oil level every time prior to using.

You can still tip it and drain through the dipstick. I use a Briggs oil collection pump. Best 40 bucks I've spent.1624428480463.png


slomo
 

Born2Mow

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I thought I had the cylinder at TDC.
Both valves were closed.....
How is it you know exactly where the valve are set, but were guessing at the c/s position ?

I think it was overfilled - a lot of oil came out.
And why are you guessing at the oil level.... when "oil" was the initial complaint ?

There's nothing quite like a guessing game where the guest withholds key information, and makes up answers as they go. :ROFLMAO:
 
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