How do I adjust the timing on my HuskyLock 435C Sergersewing machine?

I purchased a used Husquvarna HuskyLock 435C Serger from a friend it came without a manuel. It was working great then it would not make the chain stich at all .In my searching throut the machine I descovered the set screws on the lower and upper looper were loose. What is the sequince in the timing for my or any seger I cant seem to find anything to show the timing and how it works. Can you heip me please