My old but formerly reliable Hahn Eclipse rototiller inexplicably stopped running the other day - right in the middle of tilling the garden.
What I know:
1. Engine is getting gas. Gas is fresh.
2. Spark is OK.
3. Compression is 80 lbs.
4. Fresh oil in engine (always).

I'm going to change the plug, even though it looks good - maybe the insulator has a hairline crack or something (it is a Champion - not my favorite)

Is 80 lbs. sufficient compression for this 45 yr old B&S?

I will also check flywheel to see if it shifted, but there was no reason it should have.
Any other thoughts as to why it would just die without warning?

New plug may solve your problem but I dough it.
You probably have a carburetor problem, some trash could be stopping gas flow. A good cleaning and use air if you have it.

It's possible, but when I pulled the plug, the cylinder smelled of gas.
Still maybe the flow is insufficient - I'll go that route if the new plug doesn't answer the mail...

:) SOLVED!!
It WAS the spark plug - put a new one in and it started on the second pull, just like before!

Hard to believe the easy solution worked for once.
Lesson learned - try the easy stuff before you go twiddling with $h!t.
Funny thing is, the "old" plug showed no wear, although I have had to clean it more than a few times because the old engine puts out a bit more than its share of carbon and a bit of oil seeps into the cylinder, as it blows blue smoke for the first 30 seconds of operation. This tiller only sees about 10 hrs of use per year, so the plug never has an opportunity to "wear out" - likely the cleaning did more to contibute to the failure than anything else..Oh well - an easy and cheap fix and my ancient tiller lives on!