you mean when the handle is near the bottom, the reels kick but instead of spinning they more-or-less jerk maybe a position or two and immediately lock all at the same time?
if that, then take a look at the L-shaped stop bracket on the rear/bottom of the right side of the reel mech. That controls when to kick off the reels, and the right edge of the stop bracket usually aligns to the frame or just a little left of the frame edge.
if you move the stop bracket too far left, the handle will bottom out and be stuck with the reels unkicked. You have to release the handle or push the latch pawl with a long screwdriver or dowel make the game kick.