[Shiny]

Thanks for confirming the repair sleeve.

If it's already slipped it makes sense the timing mark would be off.

What I'm asking is if there's a way to tell if the assembly has degraded to the point where it's not worth saving. For example, if it's close to slipping or if the rubber has degraded enough to lose "stiffness" and allow the timing mark to bounce around more than intended.

We are told to replace old tires WELL before 50 years, so I'm curious how the rubber compound in these old dampers holds up and if there's a way to know that doesn't involve specialized equipment.

I replaced mine because the timing was bouncing at idle. This was more likely because the mechanical advance wasn't stable but at the time I had a new damper and chose to just do it.