the arm that the setscrew goes thru does not have any play. If loose ,its worn and needs replacement.
Don't know about the overheating, but the current problem sounds like a failure in the oil cooler. Oil under pressure goes out into the raw water when
I think the next most likely is the intake manifold coolant passage. There are sealant areas, that if compromised, will leak water directly into the
fixed. Used my 3# universal adjustment tool. I have a manual somewhere.
Here was the quick fix and what I feel happened, for those who maybe
Update! I rebuilt the gearbox and found no problems but the oil was very dirty. Then I reassembled and started it and the tick was back but not at idle.