first of all i dont specialize in mercedes at all, i am a engine builder but not for mercedes

well lets start, its a 1973 mercedes 250 i believe imported from germany.

it just wont start at all...i replaced coil with new one to see if getting spark and i am,,, it jsut cranks and cranks...i checked compression and nothing, i looked at chain and its still there.. soo idk whats going on here...

any help?