If your sewing machine is missing stitches, or the needle seems to be catching on the bobbin case or hook. Follow these instruction to reset the sewing machine needle timing.
But, first replace the needle with a size 90 brand new sewing machine needle. This is extremely important, the needle must be unused, and the correct one!
Remove all the thread and remove the bobbin case and needle plate. You may need to remove the feed dog if required for a better view.
This information will set the needle to the hook timing correctly.
Set the sewing machine to straight stitch with center needle position.
Turn hand wheel anticlockwise the needle will move up and down. Watch as the needle moves up and down just like the animated image below, see how the needle should go to its lowest point then up slightly, just as the hook point rotates past the needle. That hook should catch the thread from the needle eye.
Prepare the needle position:
Keep turning the hand wheel by hand, and stop only when the needle point moves to its lowest point, then moves back up - Stop turning when the needle moves exactly 2.2 mm higher than its lowest position.
Set the hook to the needle:
Loosen the hook gear or belt pulleys (usually held in place by 2 or 3 allen key screws)
Turn the hook by hand in the same direction as the machine would run (the top shaft and needle must not move), watch the hook movement as the hook point rotates behind needle point - when the hook point is directly behind the needle tighten all gears etc.
The optimum position you must achieve is the needle should be inline with the hook point. Also the needle eye must be just below the hook point.
After timing the needle to hook, the next task that may need to be checked or adjusted would be the feed timing, which is the feed dog moment to needle movement. This is covered in another FAQ.