I just got back from jet skiing for a week. Nobody has a reply? The early SHercos would spin the mains in the case. I would do a complete tear down.
The fix is ti peen the bearing location on the cases to get it to hold.
You do not have enough free play and when it heats up it starts slipping. You obviously have the levrs stopped from going back out.
If you have small hands you can slightly grind down the end of the push pins.