This is what that linkage looked like in its youth, before a previous tenant made improvements:

[Linked Image]

You need to make it look like that again. Note that the throttle butterfly is operated by a bent-wire link, not some folderol with a "weight", a "pin", and whatever other rubbish that idiot happened to have under his bed.

The part number for the wire link can be found in the Illustrated Parts List, here:

http://bsintek.basco.com/BriggsDocumentDisplay/Z6jmsHVJ1DajI.pdf

If you look on Page 5 of 15 you will find that the wire link is Item 201, and on Page 12 you'll find that the corresponding part is called Link - Governor, and the part number is 260898. I suggest you contact the On-Line store, or a mower shop, to get one - or you can probably get one from a defunct engine.

Similarly the Governor Spring is Item 209, Part Number 260041.

If you want to see what it should look like except with the governor spring missing, try this thread:
https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=61875#Post61875