# John Deere JS63 won't start - backfires....



## HawgHunter74 (Apr 13, 2011)

I have a John Deere JS63. It was given to me with the information that it wouldn't start due to a dirty carb and that the carb just needed to be cleaned.

So....I bought a new carb and bowl....new air filter housing....new fuel line....new gas tank....new ignition coil....and new spark plug. It still will not start and backfires when trying to do so....

Any idea's???? What else should I look at?:4-dontkno


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## K-B (Oct 24, 2005)

What kind of engine does it have on it? Model numbers?

Also, check the flywheel key. May be sheared or partially sheared.


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## HawgHunter74 (Apr 13, 2011)

Briggs & Stratton 
Model Series 121602, Intek 
6.75 hp
Cycle 4 
Over Head Valve

Gonna check the flywheel now key now....will report back in a few.


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## HawgHunter74 (Apr 13, 2011)

Well, won't get to check the key till tomorrow....don't have a 15/16 socket. So am borrowing one from a buddy of mine....will post up with my results.


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## HawgHunter74 (Apr 13, 2011)

Had to wait till payday to go buy a new set of sockets....


Pulled everything off and the key looks fine....and other idea's. Really need to get this mower going.


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## Basementgeek (Feb 7, 2005)

Hi 

Have you ever adjusted the vales?

If not, here is how to do it:

Repair Videos

Scroll down to valve adjustment to watch the video.

BG


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