Finally got the 5 hp B&S "L" engine to my Giant-Vac leaf blower running well, again. Thanks to everyone here for all the tips and suggestions. The problem with the engine was it hard to start and I had to keep the choke on for 15-20 minutes to keep the engine running until it fully warmed up.
I checked and replaced a lot of stuff in/on the carb with no improvement. I finally got a lead on the problem when I connected a leak down tester to the engine and heard a leak through the exhaust port. I ordered new intake and exhaust valves and proceeded to try to get the engine running by lapping-in the old valves. When I checked the valves stem clearance to the tappets, both valves were resting directly on the tappets. I ground the ends of both old valves and tried to lap them in, but they both continued to have compression leaks. As a result, I installed new valves along with a new header gasket after truing the engine head.
One pull, and the engine started. I've been running the engine now for about a week and it continues to run fine. The only thing I wish I had done to do a 100% repair was to re-cut the valve seats. I don't have the tools for that, but hope to find a good reasonably priced set to add to the tool chest.
Again, thanks for all the help and guidance.