In the electrical system and otherwise what causes a Murray 20 lawn mower 4.5 model 10H902 type 0216 not to start after changing the spark plugs and oil and cleaning the filter?

Answer 1

I'm no expert on the different kinds of lawnmower but... Test for spark by pulling plug lead, inserting a big nail where the plug would go and (holding the lead with two sticks so you don't get a nasty shock) hold the tip of the nail 1/8 inch away from the engine block as someone spins the engine. If you have a spark at the nail, you probably have a spark at the plug tip (although I have done this test and STILL found the plug was bad under compression). Do you have gas in it? Do you have an electrical safety cut-off switch on it that is in OFF position, like my generator? Do you have a gas line feed valve somewhere that was turned off after last fall's last use? Take the plug out and smell the plug hole...can you smell gas? If no, then it will never fire up. If yes, you may have cranked and cranked and cranked until it is too flooded to fire. Is the tip of the plug soaked with gas? Too much. Leave the plug out and let it dry out. If you have fire and you have fuel without flooding, you have a running engine, simple as that. CHanging the oil is good for the engine, but it has nothing to do with whether it starts or not.