Is there or should there normally be a steel washer under the gear? Could I have missed it in the rebuild? And if I did would it take this long to show itself?
There was never a washer or shim supplied or suggested. HOWEVER, back in the day roller cams were seldom used in anything but a race motor that saw regular teardowns or maintenance. Subsequently wear was likely caught in the early stages and the gears swapped out before any significant damage occurred. However, once rollers started seeing more street use and probably less maintenance, its become an issue. But one that's easily solved or avoided. Either with a steel shim or a treated steel gear.
