Carla looks after this engine. What confused you, what broke, what should it do next?
You got a 3D printer and no CAD skills? Fine. Say what you need in a sentence or two, type the measurements from your caliper, add a photo of where it goes. CADet Make builds the part in FreeCAD, checks that it is one solid printable body, and hands you the STL.
An STL you drop straight into your slicer, the FreeCAD file to tweak, and the recipe script with every dimension named. Change a number, rerun, done.
One connected solid, valid geometry, your sizes applied, print orientation. If the first build fails the checks, it fixes itself and tries again before you see it.
Not a sculpting tool and not a full CAD. Functional parts: plugs, brackets, adapters, spacers, clips, mounts. For figures and organic shapes use CADet on the desktop.