Craftsman riding mower blowing smoke


  #1  
Old 05-03-15, 08:49 PM
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Craftsman riding mower blowing smoke

Engine is a 17.5HP OHV. This lawnmower will start up and idle fine for about 30seconds and then it almost dies, and blows a ton of smoke out. It will repeat this cycle over and over again. At first I was thinking it needed new rings because it has greatly reduced power since it started running this way but the fact that it can run normal at startup everytime makes me think it may be a simpler fuel related issue. Anyone have any experience with this problem in the past?

Heres a video of what its doing:
https://www.youtube.com/watch?v=9wisalBitmk
 
  #2  
Old 05-03-15, 10:22 PM
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Check your oil. Is it thin and does it smell like gas? If so, your carburetor is leaking and you need to fix it and change the oil.

If the oil is normal, then you almost certainly have a blown head gasket.
 
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Old 05-04-15, 09:25 AM
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Ill check that once I get out there. Maybe the oil is filled with gas. seems more likely to me that a blown head gasket would leak continuously
 
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Old 05-04-15, 10:16 AM
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It does leak continuously. It fills the engine crankcase with pressure until it's more than the PCV system can handle, then it burps oil and gas out the vent system into the intake until it can close again, then it builds pressure again and repeats the cycle. This is exactly what a blown head gasket does on that engine.
 
 

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