I have no idea what engine it is but in general, for me especially if it a completely unknow engine which I've run across more than I'd of ever thought I could

first set the high end by setting it to full thottle, peak the RPM then back it off about 500 rpm with the high needle.

get the engine to the lowest possible run you can then pintch the fuel line hard for like 3-4 seconds. if it speeds up and dies it's too rich. if it just stops it's lean. righty-tity is leaning lefty loosy richens it.

get it going and lower the idle somemore and pitch it again. again does it speed up or just die. keep doing this until you can give it a good pintch with little change using 1/8 of a turn at a time.

Then richen it about a 1/4 turn

now reset the high end and recheck the low end. it will speed up very little.