Getting mower ready for first time use this year. It will make a revolution when tried to start, but that's it.
Normal maintenance was performed, changed oil, plug, air filter, charged battery.
Tried jumping the rider with my truck, same result.
Tried jumping the starter directly, same result.
Checked starter pinion and ring gear, they are OK
Can turn the flywheel by hand.
Removed the plug and engine spins freely when engine is started with key.
When the plug was reinstalled, I tried to start the engine and it makes a revolution to the compression stroke then stops. The fly wheel can still be turned by hand.
Does anyone have any suggestions?

Your valves need adjusting.

Thanks Mowerman, that's what I thought it might be or either hydraulicly locked, but after I removed the plug and spun it, locking was ruled out.
The engine is a model 31P777-0296-E1.
Do you know what the clearances are supposed to be and since that is something I haven't done before can you give me the short version of how to adjust them or point me in the direction of how I can get that info?
Thanks for your help.

Okay,
1. Run the engine for at least five minutes to obtain normal operating temp.
2. Remove the spark plug. Has to be done for each cylinder on twins.
3. Turn the engine to TDC and the 1/4", ONE QUARTER OF AN INCH past tdc.
4. Loosen the locking nut, and use a torx driver to turn the adjustment bolt.
5. Set both valves at about .006", do this by holding the feeler gauge in between the rocker arm and the end of the valve. And turning the torx to obtain a good fit on the feeler gauge. Then hold the torx steady while you tighten the locking nut(jamb nut).
6. Then recheck the clearance.
7. Reassemble, check oil level and try it out.

Thanks again Mowerman.
I found the answers to most of my questions on the Briggs and Stratton web site.
Exhaust clearance is .007" and Intake clearance is .005"
Once I made those adjustments it fired right up.
Thanks again for the help.

Opps, sorry about the miss on the " of clearance. But there has to be a tolerance and
.006" would have probably fallen within specs. Good job. I am glad you got it fixed.

Some of those engines also came out with cams that didn't have a compression release at all. If it continues even after the valves are adjusted you need to install a new cam. Hopefully not though.

I have a small question. We are having the same problem with our mower and I paid someone last year to do this. All of you make it sound simple enough but I have a couple of questions. Which valve is which? Such as... is the top one intake or exhaust and such. Second, How do I release the flywheel? Lastly, do I need to replace the gasket.

We also had the starter rebuilt and it has gone out. Where would be a good place to buy one or what is an acceptable price for one.

Thanks for everything in advance.

Mike