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2012 Briggs and Stratton model 33187 2371 G5, Craftsman yt3000 bought new in 2012. About a year ago had the common issue with the compression release so have been removing the air filter and covering to get it to spin and start. Last week it would not start so after some research I found that the flywheel had not only sheared the pin but had cracked. Bingo so a couple hundred bucks and now can only get it to backfire through carb but not start. Got fire, cleaned carbs and adjusted valves, thinking something with timing but what else is there after replacing flywheel and key. Something damaged internal. thanks in advance

Did you buy the correct flywheel? Briggs changed flywheel and crankshaft designs in middle of 2012. The flywheels are timed differently due where keyway was cut.

StarTech said:

Did you buy the correct flywheel? Briggs changed flywheel and crankshaft designs in middle of 2012. The flywheels are timed differently due where keyway was cut.

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It was the mod 571759 ordered from Briggs website and numbers matched the old one but maybe will take off and compare with the old one

StarTech said:

Did you buy the correct flywheel? Briggs changed flywheel and crankshaft designs in middle of 2012. The flywheels are timed differently due where keyway was cut.

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Looks like you nailed it, everything is exact except the keyway, about a quarter off, now what do I do with a 200 buck flywheel lol.... Cannot seem to find a different one online but will have to dig deeper, thanks for your help

Also the new torque spec is 110 ft-lbs

StarTech said:

View attachment 63437

Also the new torque spec is 110 ft-lbs

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thanks again, the 698281 is the one I need but is manufacture discontinued with no substitute but did see a couple used on ebay

Just a thought, If the flywheels are the same except for the keyway you may be able to take the old flywheel and the new one to a machine shop near you and maybe they could measure it out and cut a different keyway in the new flywheel. At that point you would have a flywheel that is new and will work without spending more money. Maybe Star Tech will know if those wheels are the same except for that keyway.

As far as I know the core flywheel is the same just how the keyway is position and cut as is the crankshaft key way and position are done. Below is from the service bulletin APSI 89.

I noticed the keyway difference once I compared. I am going to a local shop and see if I can trade new one for a used one. Probably best way to recoup some of the dollars

Correct flywheel and key installed but with the same results, think it's time to shop for a new mower

jbell19 said:

Correct flywheel and key installed but with the same results, think it's time to shop for a new mower

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My mistake, key had sheared added lock washer to flywheel bolt and tightened nut to specs and she fired

It will shear again
You need to remove the flywheel and lap the flywheel to the crankshaft with some extra fine valve grinding paste
Check for any lips or burrs before you start & file them off .

or get a second set eyes on the problem.