1650 wont restart
 

I was pushing snow yesterday with the 1650 that I bought this past fall, and I shut it down after an hour or so to check the oil... It would not restart. I pushed it back in the garage and it restarted today. I pushed more snow, and had it running for probably 2 hours or so, let it sit at a dead idle, went to throttle back up and it died...no restart. Any ideas?

Sounds like a fuel issue--either a vapor lock or, more likely a plugged fuel intake screen in the tank Next time it does it, pull the fuel line off the carb and see if it's flowing freely. If it's not flowing, then pull the shutoff out of the tank and clean the screen. might want to plan to replace it.

Key detail , sorry I was distracted the first time around. The engine wont crank. Turn the key to start, the engine will turn about 1/2 rev, let off key and it returns to the original position. That is both yesterday when I shut it off, and earlier today when it died on throttle up. However, it did start this morning, more or less normally

I'd start with battery connections, grounds, etc.

If the battery and all the connections are good and it still does it I'm wondering if the float is stuck open and filling the combustion chamber with fuel and that's why it wont turn over? Does the oil smell like gas? I've seen this before

ACR?
 

Does your engine have Automatic Compression Release? The heat sink could be creating a sticking valve which defeats the action of the ACR. The valve frees itself on cooling. Just a thought.

I am going to check electrical and sniff the oil tomorrow, I hadn't thought of the stuck float actually flooding the cylinder. I am pretty sure it does have ACR, also another good idea. I will start with elecrical, since I had noticed some loose bolts. I am pretty sure I will be doing a rebuild when it is warmer.

all electrical connections are tight, oil is just oil. went to crank and there was a screeching noise after it started to turn, so I stopped. I was considering a rebuild or repower, looks like I will be doing one of them sooner than planned

Sometimes those starters will make a screeching noise while they turn over. May just want to pull it off and lubricate the bendix.