It's a common failure on these Maschines from the 60s and 70s that the small plastic part that pushes the motor to be easy on the rubberdrive, breaks after the years.
This part replaces it.

Have fun with your awesome highquality sewingmachine!

fullmetal P3

No

100%

The centerbore may need to be reamed or rasp to size.
The Bore for the Thread needs to be bord to 3.3mm and than threaded M4.

Smmothing the ramp makes a better userexpierience.

I put a 1.5mm thick M8 washer behind this, to give it some backing.

allmost identical to the original, but I added a small dent on the highest position to prevent from snaping back.