One of the most problems in a sewing machine is the timing. Timing is very important in threading to meet the balance of the stitches in the fabric, and it should ensure that the parts of the machine are working synchronize. In general, all different types of a sewing machine has the same process for adjusting and repairing the timing however the method of installing, removing and modifying the part has a different way in each different machine. So it is recommended consulting first the company about the manual process for your machine while checking the stages and fine adjustment for the timing of the machine. Check this site to know the stages in repairing the timing of the sewing machine.
The first stage is to diagnose the timing issue by working and test the position of the needle and the hook shuttle to determine if there is a need of adjusting in timing. Upon doing you need a ruler to estimate the measure for the timing settings, position the needle in the lowest by using the hand wheel and then uplift it up to 3 over 32 inches. Ensure that the hook shuttle riches the needle over the eye of it while in the position. If didn’t rich you must adjust the timing. The second stage is the timing of hook, you need to position the needle bar at lowest by use of hand wheel, less tight the gears in the button part of the sewing machine and lastly adjust it when the needle and the hook are apart correctly.
The right estimation of distance either from 0.04 mm up to 0.01 mm or 0.01 up to 0.16 depends on upon the manual of the machine. The last stage is to resemble and operate the machine, by slowly tighten the screws and no replacement of parts. Clean and use oil of gears but remember use oil that appropriates of your sewing machine, change the switch plate and covers and last re-thread your machine and try some test of a piece clothes to check if you solved the timing issue.
In repairing the sewing machine is quite complicated, it is important to know the mechanism of the sewing machine, so it is not hard to identify the problem.