Damn, good job. I was struggling with an old Briggs and Stratton and haven't had time to get it working yet. It's probably from the late 80s early 90s. (Snapper brand, nothing fancy, no self drive or what not, wasn't out yet I don't think). I pulled the carb out and tried cleaning it with gas/starter fluid, replaced the spark plug. Got it to start up and start running but I assume it was running off starter fluid from the carb. It cut itself off after about 15 seconds (which was longer than I expected for just running off the carburetor ether. The springs are probably all stretched out. Need to try to get new ones in spring and actually put some time into it. It's hard to convince myself to put the time/money into it when it's that age