The good news is you can find manuals for the Elna lock L2 Overlocker, but the bad news is they aren't free.
Even photocopies or PDF documents of the Elna Lock manuals sell for a couple of dollars online, from sites such as http://sewingpartsplus.ecrater.com/p/8446011/elna-lock-service-manual-l1
Seems kind of unfair to me that people are charging money to share information about manuals, but as many of these models aren't made anymore, the manuals are pretty hard to come by - and these capitalists have realized this!
I also found a similar question on Blurtit which received a similar reply about a Elna Lock manual, so you are not alone. Might be worth a read as it goes into a bit more detail;