Outdoor Power Equipment and Small Engines - Engine Oil Consumption

thanks in advacne for all responding
I have a cub cadet riding mower with a kohler 4 cycle engine
family skk162441g2ra
model ch18s
624cc
serial #2604600757

has in excess of 700 hours for the last mowing season I have been using quaker state synthetic oil, now I am noticing oil consumtion and blowing out the carb into the breather

any ideas......mow 3 acres at a time

new here so saying thanks for a forum like this again
woodhill

Hello Woodhill!

Welcome to the small engines forum at DIY!

What weight oil are you using? Is the oil level overfull? Those things can help determine the cause of the problem. It could also be a restricted air filter, blown head gasket, pinched breather hose, engine wear.

Its probably most likely that the engine has to much oil in it past the recomended limit.

thanks for the response ,,,,, oil level is correct using quaker state synthetic 5w20 as per specs.....my thought are a rign bad or crack in piston ??????
how do I check for these??

You have to take the engine completely apart to check for a crack in the pisten. But, I don't see how a cracked pisten would blow oil out of the carb.

Are you sure the manual reccomends 5W-20? That should only be used in extreme cold temperatures...if ever. That is too thin. I would drain it and put in straight SAE 30w. If you look, I think you will find that the only time a multi-weight oil is reccomended is when the temps are quite cold. Some manufacturers even state that use of 10w30 oil will result in oil burning. There are problems with using multi-weight oil in small engines, as the viscosity index improvers do not fare well in the heat of an air cooled engine. The oil reverts to a 5 weight oil before long, and that is definitely thin enough to cause some smoke. Try that first. I doubt a cracked piston is your problem, but that would definitely let oil blow into the carb, as would a bad ring, blown head gasket, scored cylinder wall, pinched breather hose, etc...