There are 2 plugs one is a 14mm and the other a 17mm on the bottom of the case.. . Which is the oil drain? the 17mm one has 3 small bolts holding it up. Like a small lid. I can't remember which one it is. I have the filter and oil . My darn memory is no good any more. Ken

 

its the 17mm. the 3 little nuts are there to remove the screen type filter thats in there.

 

thanks Mudslingingfool.
I have changed the oil and filter before but I know I haven't removed the screen. You can tell I am not much of a mechenic, hell I can't even spell it. But will do it tomorrow. Will also write it down in my owners manual so i don't forget. Thanks again , Ken

 

I believe you need to drain the oil from both plugs. Same oil in both but the way it is put together you cannot drain all the oil from one. That is the way the 300's are. Same basic motor.