the mower was sputtering in thick grass and stopped. it had done this before in tall grass but started up again. I tipped the mower sideways to clean under neath and when I put it upright, oil was all over the mower deck.I opened up the choke box and oil was dripping off the filter. any suggestions appreciated. mower is one year old. tx

 

Tipping the mower let oil run into places it shouldn't. You'll probably have to replace the filter unless it was foam. You may have to clean the spark plug, pull the engine over severl times with the plug out, then put it in and prime it and see if it will start. Leave the new air filter out until it has run long enough to quit spitting oil on it. It will smoke terribly for a minute or so. Make sure the oil is full before you start it.

 

Tipping the mower to clean it is not uncommon. But I suspect you tipped it to far and in the wrong direction.

 

Look at the carburetors location on your mower. When you tip your mower tip it so the carburetor is up not down.

 

Tipping a push mower on either side can cause issues, if not from oil, from fuel getting where it should not be.
Raise it from the front and secure the handle to the floor is the safe way to access the underneath.