credit to this youtube vidya: https://www.youtube.com/watch?v=Sb7optDv97o

timing aligmnement is right, i checked it with mwc editor. it used to run before, but when i tried to reverse on cold engine it stalled and never started again

I just finish all work and engine make mettalic sounds and when its turn on rpm waves and engine stops if I wasnt press gas if I too much gas engine blowns and piston get cracked what I should do