Hit a board with my lawnmower

[crazy charlie]

I didnt pick up one of the boards that my boat was sitting on over the winter.Went over it with my craftsman mower and it stopped dead when it hit.Had to replace the blade.Now it wont start.Did I screw something up big time??Pull start feels fine.Charlie

 

[Scott Danforth]

you most likely sheared the flywheel key. available at lowes, home depot, ace, etc.

 

[harringtondav]

Also remove the spark plug, and tip it on which ever side puts the carb up. Straight up on the front wheels normally works. Pull the starter to see if the crankshaft is bent. There are many internet small engine part suppliers, if that turns out to be a problem, and if you're willing and able.

 

[dwco5051]

you most likely sheared the flywheel key. available at lowes, home depot, ace, etc.

Yep, about 95% chance it was the key. Be sure to pick up the new key that is soft aluminum in the lawn and garden section. A steel key will guarantee that the next board will cause major crank damage.

 

[bigdee]

Hopefully after you replace key you won't discover your crank is bent. I hit a small stump with mine (Tecumseh 6.5 hp) and bent the shaft where the blade mounts....It did not shear the flywheel key either. I used it like that for awhile until the vibration gave me carpal tunnel. I replaced engine with a HF.

 

[SkiGuy1980]

A few years back I took the first spin around the property on my new John Deere... and promptly caught the edge of a stump. I thought it just bent the blade, but it actually bent the spindle too (about a $300 thump). Hope yours works out.

 

[Redfred1]

A few years back I took the first spin around the property on my new John Deere... and promptly caught the edge of a stump. I thought it just bent the blade, but it actually bent the spindle too (about a $300 thump). Hope yours works out.

Sounds about right; and not warranty repair. L/M stuff is a lot cheaper online.

 

[Scott Danforth]

I used to sharpen my blades and use the push mower to trim the bamboo stumps (easier on the yard than pulling them out with the truck). if you got too aggressive lowering the blades onto the stump, it would shear the flywheel key.

 

[bigdee]

That is the best scenario but don't always count on it shearing. The shaft is tapered and depending on how much the flywheel nut is torqued determines if key will shear. Best to have a soft key on blade spindle. Some blades are un-keyed and are held on with a single bolt with a belvue spring washer to allow blade to slip if it hits an obstruction.

 

[Scott Danforth]

you assume I care about the lawnmower. I get them free from the side of the road. no one down here understands on how to maintain a mower. plugs and the occasional carb cleaning is usually what they need.

 

[bigdee]

you assume I care about the lawnmower. I get them free from the side of the road.

My favorite place to shop! A friend found a 2 year old riding mower someone was throwing away because he replaced battery and it would not start. Turned out that he put + - cables on backwards! My friend switched cables and it started right up....it even had a full tank of gas!

 

[crazy charlie]

Thanks guys,any way to tell for sure the shear pin is needed w/o taking things apart?? Like a prop on a small outboard motor?? I am kind of a hack when i start disassembleing things

 

[bigdee]

Thanks guys,any way to tell for sure the shear pin is needed w/o taking things apart?? Like a prop on a small outboard motor?? I am kind of a hack when i start disassembleing things

Not really. You will have to, at least remove shroud cover to see magneto. With magnetic part of flywheel in front of magneto cylinder should be at top of its stroke and both intake and exhaust valves should be closed. You can remove sparkplug and rocker cover to do this BUT if were me I would just pull the flywheel.

 

[Scott Danforth]

Thanks guys,any way to tell for sure the shear pin is needed w/o taking things apart?? Like a prop on a small outboard motor?? I am kind of a hack when i start disassembleing things

nope, pull the shroud, pull the tank, pull the recoil cover, unbolt the flywheel

5 minute job at best on a briggs