it was mowing along great then all of a sudden a loud bang and oil was coming from the crankcase breather and pushing out the valve cover, so i shut it down and it will still start but won't move past idle and it sounds rough, the mower was ran with out the shrouds and covers for a while, i was thinking maybe it got to hot, any suggestions would be very helpful, i have pulled the the head and inspected it and didn't see anything i thought would be causing this so i replaced head gsket and it was still blowing oil, not sure where to go from here thanks

did you pull both heads? and if so what did your cylinders look like?when you had the heads off did you manually turn the engine over to see if both pistons where moving ? sounds to me like you have had one of the cylinders fail or a rod break you may need to go much deeper then just the heads on this one.

no i didn't pull both heads i just pulled the one that had oil coming from it, it, the engine will fire and run just idles though and spews oil out the crankcase breather

It could very well fire and run,but if you have a cylinder that is not working your building oil pressure. and if you have a piston that is stuck at the bottom of its stroke that oil is not going to that cylinder it may be going out of your breather or valve cover (just my thoughts on the oil coming from the valve cover and breather).Or you could have stuck valves on the side you didnt check and its building excessive crank case pressure. does it sound like its only running on one cylinder ?either way your going to need to pull the other head qand go deeper into this.

i pulled motor and it had a broken governor gear so i replaced it and put new pistons in it and reinstalled and now it won't idle just runs at full throttle and it sounds like its gonna blow not sure where to go from here any advice would be much appreciated. thanks

correction i didn't put new pistons in it i put new rings in it.

i pulled motor and it had a broken governor gear so i replaced it and put new pistons in it and reinstalled and now it won't idle just runs at full throttle and it sounds like its gonna blow not sure where to go from here any advice would be much appreciated. thanks

Your governor is not set correctly, go to this link section 5 page 30 and follow step step the governor setting proceedure

http://www.kohlerengines.com/onlinecatalog/pdf/tp_2450_c.pdf

thanks i'm sure that is the problem thanks for the help, i'll let you know if this does it

governor was just adjusted wrong thanks for all the help guys