6.75hp B&S 'popped' and died

[maddogandnoriko]

I have a Craftsman self propelled mower with a 6.75hp Briggs & Stratton engine. I was mowing last week and after about 1/2 hr. it 'popped' and died. It had started to rain so I finished up with a neighbors mower. I took it out today and gave it a couple of pulls. After a pull or two it backfired. Another couple of pulls and more backfires. I think it was backfiring from the muffler, but not sure. I pulled the plug and put my thumb over the hole and gave it a pull. No compression at all. This mower is about 1 year old. I think that is all the info I can give...except the model numbers.

Mower model#: 917.370430
Engine model #: 126M021525-F1 11110858

So where do I begin pinpointing and repairing the issue?


Thank you for your time,
Todd

 

[Rivets]

First thing to do is check for a sheared flywheel key.

 

[briggs]

First thing to do is check for a sheared flywheel key.

yes check the key if the key is ok check the valves one may be stuck open i have seen this happen a few times ...One time i had one that the seat kept popping out i took a punch and dimpled the outside of the seat it still popped out it was a 6.75 also let us know what u find and please post pics

 

[Raw Dodge]

It sounds like you blew the head gasket...it's highly doubtful you sheered the key way and even if you did you'd still have compression but no starting...

 

[maddogandnoriko]

I finally got a chance to work on this mower. Briggs was right, one of the valves was stuck open. I lapped the valves, cleaned all of the carbon off and replaced the brother gasket and head gasket. Runs great now. Thank you guys for the help.