Now YOU made me snort!
Have exact same problem, I swear it wasn't me that did it!Haha, sumtimes ya get lucky, eh?
Some bonehead (me) over-tightened the tach cable to the adapter, probably to stop a leak without first looking at a parts diagram to see where it might be leaking from. When I removed the tach cable the adapter spun right out with it, and it was locked on there real good. Been spraying with PB Blaster for a week, nuthin, without wrecking the threads.
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Was by a specialty hardware shop today and picked up a couple M16x1.5 jam nuts. Didn't have a lot of thread to work with. As it turned out the recess in these nuts was a large enough diameter to fit over the tach drive cable knurled connector.
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Badaboom badabing, spun right out.
It's between 16 and 18 tpi. 1inch is 25.4mm. Divided by 1.5 is 16.93 tpi.What's the other one, 16 t.p.i.? 5/8-18 might be closer. That's a 5/8 fine thread.
Well, I'd have to say the metric 1.5 is the clear winner in that comparison...
just wonder if the entire rings should have been sanded very lightly on their upper and lower perimeter edges??