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bogie1162 · Jul 23, 2009, 06:58 PM

My 14.5 hp briggs started blowing oil through the breather after an overfill. Oil level corrected still blowing oil.
Thanks for any thoughts.
RLS

crigby · Jul 23, 2009, 09:28 PM

Hi,
It probably got places it should not be and will either blow out or return to the sump after a bit of running time. Messy but not a real problem unless you detect the oil level going down to match it.
Peace,
Clarke

bogie1162 · Jul 25, 2009, 12:10 AM

Originally Posted by crigby

Hi,
It probably got places it should not be and will either blow out or return to the sump after a bit of running time. Messy but not a real problem unless you detect the oil level going down to match it.
Peace,
Clarke

Oil level is going down to match it.
Rls

crigby · Jul 25, 2009, 05:05 AM

Hi,
Not good. It generally means that the integrity of the engine's sealing properties have been compromised.
Let me explain. The engine produces power by trapping an air/gas mixture above the piston, compresses it and the ignition does what it says, ignites it. This creates a controlled explosion the forces the crankshaft to rotate (and all connected parts to move) form the power produced.
During this time the piston rises and falls in the cylinder and air must either enter or exit the area below it. Controlling this flow of air is the job of the breather. The crankcase will slightly pressurize, which hurts nothing, and can force oil out if there is a path.
An air leak that allows air only in will have the effect of over-pressurizing trying harder to push the oil out. Piston rings that allow too much of the combustion products past them will do essentially the same thing.
A breather that plugs in one directiion could do this. A gasket that has been blown in or out of place can do this.
My suggestion at this point is to remove the hood to get good access and view, wash entire machine around engine (not running and cool), check oil level and get it "spot on" and run the engine while watching carefully to see exactly where oil is coming from. It can be blown about quite a bit.
Briggs has the unfortunate characteristic of blowing the sump gasket right beneath the bottom of the cylinder. Not say that is what you have; just pointing it out. Leaking head gasket could pressurize the crankcase.
Of course, I am at a keyboard far from this engine, so I am unable to see, hear or anything else to ascertain the conditions save what I read. Good luck in your exploration. Air leak is the indicated problem.
Peace,
Clarke