lawnmower engine problem

hi, I have a crafstman lawnmower model # 917-387050, that doesn,t want to start. I check for compression and is a good compression, I check for spark and is a good spark. I rebuilt the carburator. I took the mufler out and was a lot of carbon deposit. When I started kicks back can sombody tell me what else I can do. thanks

guillermo

 

When you say kicks back, do you mean it rips the starter cord out your hand?

 

yes, the lanmower rips the cord out my hand

 

You have a pushed timing key. The last time you used it, did you hit anything?

 

Check Mowr Blade it could be loose causing the same problem

 

I agree...one or the other is wrong...most likely a loose blade...or could it be missing?

----NOTE----
I merged this thread with your other....please use the reply button each time you want to respond to these messages, rather than asking a new question. This keeps all the info in one place instead of several different threads, which makes it much easier to figure out your problem.

Thank you!

Cheese

 

More than likely a Briggs on your mower? I would say without a doubt..well a very small one anyway...lol..that you have a sheared or "pushed" flywheel key...typical of any mower that has come into contact with any foreign object...a small dog bone can do it....trust me...my dog leaves them where I cannot see them...maybe I should mow my lawn more???

 

you will probably need to take it to your local shop to check, as there is a special wrench(easy way) that takes off the starter clutch in order to take the flywheel off...

 

Hello diy small engine members and members posting replies

Has anyone ever thought that it is very possible but may not apply specifically to Guillermo but may apply to other readers of this topic, what is meant by a "pushed" flywheel key?

It is very possible other less knowledgeable small engine owners may not have the "Foggiest" idea what the mechanics term a "pushed key" means?

Therefore, lets attempt to fully explain the terms or use generic terms the average layman can understand. Doing so provides the best possible service to all members and saves space in the forum questions.

I also highly suggest explaining in details as many as possible solutions to a question as possible in one reply. These one liner reply questions does not provide a positive solution, professional appearance or the impression of the quality a professional has.

Now anyone care to explain what a "pushed" keyway is? I know and you know but other readers may not.

 

Good point Tom,

The term "pushed" and the term "sheared" both apply to flywheel keys. Sheared being ovious: the key has been sheared into two pieces. Pushed means that the key has begun to shear, but still remains in one piece. The part of the key that touches the flywheel has moved in relation to the part of the key that contacts the crankshaft. The movement wasn't enough to "shear" they key, but enough to distort it, "pushed". Many times, when a flywheel key is "pushed", the engine will still run, but not well. When the key is "sheared", the engine usually does not run at all.

Hopefully this is a clear enough explanation for those who do not know.

 

Thanks, for you advice I had a flywheel key shrered. I took it a part and replaced it.

 

Good job!

Glad we could help!