Timing Your Crosley

What is the best way to check and adjust timing?

An approach I have used for years is to connect a tachometer with a large scale so you can see small changes in RPM. Set the idle or block the accelerator so the engine is running around 2000 RPMs, you want to be above the advancement mechanism. Now rotate the distributor for maximum RPM and you are done.  While you are at it touch up the main jet on the carb to see if you can get any additional RPMs from that. Reset Idle.