Gas is relatively new. I think the exhaust valve is a good idea. That is what it acts like because the small backfires are coming from the exhaust versus the intake (can see a puff of smoke). Rdaystrom - can you tap on it through the plug hole?

The "slop" may be either a loose blade (tighten the blade retaining bolt) or a loose/sheared woodruff key in the crank adapter that the blade bolts to (replace the 1/4" key). The crank itself wallowing around in its lower bearing support indicates bigger problems and the need to tear it down for inspection/rebuild. If you do have the Suzuki 47PZ2, you have a rare bird indeed. This was the first year of this engine series (1983) and the only year to use mechanical points triggered ignition. The following years 1984-2003, the 47P used solid state ignition, which used a small transistor mounted in the coil casing to fire the ignition ..which was prone to heat/vibration fatigue and often failed - see other threads on here & elsewhere about expensive 47P coil replacement and attempts to save them by heating them in an oven ..all thanks to that dime sized transistor that you don't have to worry about.

Compression is the secret of the internal combustion engine. The fuel/air mixture in the cylinder must be compressed to be powerful when ignited. Compression occurs when the piston rises against the closed intake and exhaust valves. It's measured in psi and every engine has a normal range in it's specs that can be measured. The problem with measuring it on lawn mower engines is they all have a compression release mechanism for easier pulling of the starter cord which obviously would give a false, lower reading. I actually don't know how the mechanics get around this to find the true compression. Anyway, engines can lose compression from wear and faulty valve timing. Usually a lawn mower engine with low compression would indicate a new mower needed, but in a few cases low compression can be caused by hard carbon in the piston rings which doesn't allow them to expand and seal the cylinder. There are several brands of solvents for internal engine cleaning. The best in my opinion is 'KREEN' by Kano Labs, the makers of 'KROIL', a well-liked penetrant. I would use 'KREEN' as-directed in any engine I suspected of low compression. If it doesn't help, repair/replacement is indicated, because lawn mowers are basically cheap, and you can't justify spending hundreds on engine repair or replacement. The exception would be if you had a premium mower with a good deck and drive system that you really like. An aluminum-deck Super Recycler could be in this category - it all depends on how much you want to spend on it. I think your mower should have lasted longer. Cutting only a tad over one tenth acre every other time would constitute light use in my book, and most any mower should last almost indefinitely under those conditions WITH THE PROPER CARE. However, you can't overlook the possibility of a bad engine from the factory that may have a problem that just took some time to show up.

I was out of town a couple of days and haven't been able to respond. Thanks for your response. I tried to be very careful not to turn or move anything. I did not check the timing marks when I put the cover back on, I only focused on getting the plastic governor gear meshed properly. I don't even know where the timing marks are. Considering that it won't even try to start, gets a good spark, and after pulling the cord numerous times gas will be visible in the carb cover around the choke plate, along with an occasional backfire, it does sound like the timing is off. Do you have any advice on setting the timing or maybe a website that might help? Obviously, I'm not an expert mechanic and hate to remove the engine again, but it looks like that's where I'm headed. Thanks again.