Screw cap

The worst here was "lawnmower repair man" idea of dropping the lower crankcase, to replace a blown secondary drive output bearing, reassemble with as much adhesive as could be purchased from 10 auto shops in the area, took me a week to clean out the residue and clearance issues ( spun bearings ) the man was a maniac, could have cost someone their life,

Reds post is impressive all the same, the crank sludge traps must have been a treat also... better you than me Red, good man. j
The first engine rebuild on my 64 Bonnie the idiot used Stag, it sets rock hard with zero give and does a horrible job stopping leaks compared to more modern gasket sealers. I was chipping it off for days on the next rebuild. I think it was invented for plumbing originally. Absolute crap stuff.

Not if you use it for the purpose intended… screw on plumbing fittings.

Let’s not forget though, if you were stuck at Eucla WA, trying to reassemble an engine to get you to civilisation, Stagg paste would be a blessing.

Hard to know what the circumstances were. Clearly, not something that would be used if in a professional workshop

FFS, I used a cornflake box, cut with a pocket knife in the middle of BFN as a Mini head gasket at 10pm. Just to get me home.
Didn’t work very well, but got me home.

If I had died before addressing it, the next owner would have been …. WTF???
Apologies for tonque in cheek 'observation/question', about the red bits. The black bits though look like what well known engine builder Harry Pellow (of 356 Porsche fame) would call "dingleberries". Whatever that means. Can't ask him. Long dead. I used to chat with him at swap meets.
I've seen overhead lubrication halted by sealant in oil passage. Silicone plug pretty much. Total top end destruction.
Loctite (574 I think) as used on air cooled Porsche case assembly has worked well for me.
Dingle Berries:- slang : a piece of dried fecal matter clinging to the hair around the anus. Get over the ick factor and check your pet's rear regularly to make sure no dingleberries are dangling from his fur.
Laverda is departing
Referred to as a Dag in Oz. I watched my first Cruching, cutting the dags off to avoid Fly Stike when was a young kid on the family farm.