I've got a valve spring compressor, the job would have been a real pain without it. The suggestion to use magnets to replace the valve keeper is wonderful, I hadn't thought of it but I am certainly going to try it as I can see replacing those is going to be very un-fun.
Lapping the valves was part of the plan before putting it all back together. I wish I knew how many hours were on it since it's last major service as that would really help determine if this is 49 years worth of gunk, a couple years, or a couple of hours. A bit more testing shows the cylinder does leak pressure, but I am unsure for how long a B&S 170401 should hold compression. If I seal up the head and turn it for compression, I can hear the air in the cylinder slowly escaping into the crankcase. The repair manual suggests that if it holds long enough to make compression (i.e it bounces when turned), it's good, but if this is an issue I'd rather resolve it now. I am wondering if there isn't some wear to the cylinder after all, any advice?
Edited by dtsh, July 13, 2016 - 02:29 PM.