Speaking of end-play. How does everyone check their end play? 

Do you have a fancy gauge, do you do the goofy Muir thing, or do you have 
some other method? 

(I must confess that I don't bother checking mine unless I've spit the 
case...)
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I havent done this on a pancake, but on an upright you must do it with the
flyheel on.  Grab the crank pulley with both hands and push pull.  Does it go
thunk thunk and move half an inch?   garbage.   Does it not move at all?
  Take a big flat screwdriver and pry the flywheel away from the case. There
should be a tiny amount of endplay,   thunk thunk is junk.   rebuild that
bottom end.   You can seize yr motor by building it without ANY endplay.