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Small Engines (Lawn Mowers, etc.)/Smoking and leaking oil out of exhaust


I have a 16 HP Kohler OHV engine. It recently started smoking when i started it. It now appears to have gas and oil leaking out of the exhaust. The smoke appeared to be blue. It had plenty of oil and i service it well. Any idea what it is.

thanks jd

Hi  JD
has the air filter been installed all the time ?
you mentioned serviced it well,  did you perhaps over fill the crankcase with oil , ?
does the oil thats in the crankcase smell like petrol?  and very thin , dripps off the dip stick  very easily ?

oil may have been forced through breather and carb,   check carb for oil,check fuel needle valve for sticking and needle / seat for sealing  off the fuel flow -  check combustion chamber  for  oil as well  by removing plug , and turning engine over ( make sure no spark occurs incase   plug ignities  fuel outside of engine when turned over , if its been wet-sumping),to clear anything that may or may not be in combustion chamber,  check air filter for oil on the element!

could also be a blown head gasket , has the unit been low on oil @ any stage  and overheated ?
it also could be a breather system not working / or blocked / restricted , building up pressure forcing oil past rings, breather reed are under rocker cover on the cylinder head  

here is website for parts breakdown

select  model and spec from the list that matches your engine eg ch/cv5 - 16, then  cv16
then select spec number from list

have a look and let me know what you find , i will try help further

cheers paul  hope it helps  

Small Engines (Lawn Mowers, etc.)

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Briggs and Stratton MST qualified Tech - Certified Kohler Expert Tech 12 years experience in repair of Small Engines -Briggs,singles, twins Kohler, Honda , Kawasaki ----Husqvarna chainsaws and trimmers -shindiawa -chainsaws & trimmers etc Walker Mowers - Kubota Ride ons - Husqvarna ride on and outdoor power equipment, -Mtd Ride Ons, Push mowers etc


Briggs and stratton MST qualified Tech - Certified Kohler Expert tech 12 years experience in repair of small engines Husqvarna chainsaws and trimmers -shindiawa -chainsaws & trimmers etc WALKER zero turn mowers Kubota Ride on mowers Husqvarna ride on and outdoor power equipment Mtd Ride Ons, Push mowers etc some experience in 2 and 4 wheeler repair - Honda, Suzuki , Yamaha

Qualification - Briggs and stratton Master Service Tech 2005 onwards Qualification - Kohler Certified Tech Qualification - Mito NZQA National Certificate Outdoor Power Equipment Basic automotive trade skills & year 2 & 3 of Motorcycle engineering

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