# 16.5hp Briggs smoking under load



## shark (Feb 18, 2008)

I have a Ace riding lawnmower. When I engage the mower the engine starts to smoke. I checked the blade spindles, they both spin free. I also checked the breather on the side of the block. Anyone have any ideas? Thanks Bruce


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## glenjudy (Aug 26, 2006)

What color is the smoke?


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## shark (Feb 18, 2008)

Its blue smoke. I took my air cleaner off. Started the motor, ran good. I took it on the lawn and engaged the blades. It started to smoke again. There was oil coming from the breather tube going into the carb. Thats were the smoke is coming from. But were would the pressure in the crankcase be coming from? I checked the oil level, and it is just at add. And why does it smoke when I kick the blades in? Anybody have an idea? Thanks Bruce


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## 30yearTech (Sep 14, 2006)

What is the model and type number of your engine. I suspect it's an overhead valve design, and your issue is likely due to a leaking head gasket.


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## shark (Feb 18, 2008)

Yes 30yearTech, it is a overhead valve engine. The model is 313777. The code is 981105ZD


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## shark (Feb 18, 2008)

The type is 0112-E1. Thanks Bruce


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## 30yearTech (Sep 14, 2006)

The color of the smoke indicates that it's oil that's causing the smoke. These engines are prone to leaking head gaskets around the push rod galley. This will cause pressure to build in the crankcase and oil to pump out the breather and past the rings. It is more prevalent under a load. You should pull the cylinder head and have a look, a new head gasket runs around $10.00.


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## shark (Feb 18, 2008)

Thank you 30yearTech. I will get a gasket tomorrow. Is it a bad idea to spray off the motor when it is hot? Bruce


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## 30yearTech (Sep 14, 2006)

shark said:


> Is it a bad idea to spray off the motor when it is hot? Bruce


I would not recommend it, I would wait until the engine is cool. I would also not recommend spraying the engine with water at all, unless you are going to blow all the water off with compressed air and dry it up good. Water tends to get into areas where it will cause corrosion to set in and can cause issues down the road.


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