Small Engines (Lawn Mowers, etc.): Snapper RP21500, push mowers, leak oil

Question
Snapper RP21500 model
Serial is 45108075
The engine on this wont start.  Last year it would blow smoke and leak oil.  I have a feeling that the engine needs to be replaced.  I am looking for a more powerful engine for it.  It seemed underpowered with the 5.5hp engine on it. Is there any suggestions that you would have for a different motor.  This is the self propelled model.
Thanks in advance

Answer
Bryan

Sounds like the engine has seen its better days,you

Your original engine should be Briggs 128802 please check the engine number to make sure that these will work for you.


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