This is an axis stop so the "dog bone" doesn't fall, along a crank to rotate the gear.
Feed rate 50 %, nozzle temperature 200°C, bed temperature 80°C (glass bed). Nozzle and bed were pre-heated for 15 minutes.
This model is for the 100 % dimension size engine, adapt the size to fit that of your printed one.
Designed with Google SketchUp.