Stop in for a cup of coffee
Amazon.
MG Chemicals 408C Rubber Renue, Rejuvenate and Restore Rubber Belts, Platens and Rollers 125mL​
Visit the MG Chemicals Store
Stopped by the garage this morning to do some investigation.
Looks to me like the damage is because the rubber connection isn't strong enough. The oil and ATF may not have helped but the interior is dry (not gooey). Gooey and slimy are technical terms - yes?
In this floppy disk camara photo you can see an original from 1988. It's deteriated but didn't rip through. Hmmmm.
My new opinion is the replacement insulator needs to be reinforced.
May try filling with Devcon Flexane 80.
There's a review on 'zon for Flexane 93 where the guy used it for motor mounts.