I have a Honda self-propelled mower that is 3 years old. At the end of last summer it began to run rough and chug. I changed the spark plug and air filter and that seemed to help for a short time but then the chugging started up again and by the end of the summer the mower wouldn't even start. Any ideas?

 

 

you gotta put a b18c1 in it to make it run right.

 

It' a combustion engine so for it to run properly it needs: spark + fuel + air.
If the gas in it is old empty it all out and fill with fresh gas.
Does it have a manual or automatic choke?
First clean or replace the air filter. Test spark quality: remove spark plug and check for fouling on electrode. Clean the spark plug with a brass bristle brush, insert it into spark plug wire and lay it against the mower frame (make sure frame is clean). Pull cord to start (it won't) and check for spark . Replacespark plug if no spark or replace plug if fouled or hasn't been changed in a long time. Also, check spark plug gap on old plug and new (if purchased). Try cleaning carburator with this (or similar):http://media.tractorsupply.com/is/image/TractorSupplyCompany/4454447?$300$

Idle and or air screw may be out of adjustment.
Carburator may need to be rebuilt or replaced if engine keeps stalling.

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