Does anyone know if you can run a helix on a MX3 ?

What I've tried doesn't seem to work. I can post a 3D ARC via the 18 or 19 plane, but for some reason the code I post for a G17 helix doesn't work.

The ARC movements are X Y Z I J

I've been told I need a K

So it would be X Y Z I J K .

If anyone has worked with a MX3 and can help please.