Engine Engine Won't Start

I took my mower (2006 Husqvarna 42" tractor) out of the shed to tune it up for the season. It started right up. I drove it out of the shed so I could work on it and left it in neutral while I ran to grab a rag. I was greasing the fittings when it started to make a clunking noise and suddenly shut down. Is sounded as though there was a broken belt flopping around in the engine. I tried to restart it, but it wouldn't turn over. I checked the oil and there was none.

I am wondering if I overheated the engine and cracked it. Possibly no compression in the engine?

Any thoughts? I grabbed a video and posted it on youtube: https://youtu.be/m5uHhp5w4IM

Yes some thing is broken inside the engine.
With luck it will just be a con rod
Pull the engine then pull the sump cover off take some photos.
Remover the carb by pulling the manifold off thus all the controls will be in the right place when you reassemble it.

You can confirm this bu pulling the plug, placing something down the plug hole them turning the engine over by hand.
The piston should come to the top of the cylinder once every revolution.

However, rod broken or not the sump will have to come off.

Sounds like a plan. I'll pull it apart and post up with my findings.