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Old 10-11-2017
boscoe99 boscoe99 is offline
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Join Date: Jul 2013
Posts: 8,504

Originally Posted by panasonic View Post
A pair of thin nose needle nose pliers and you should be able reach in a hole that size and grab the tang.....wiggle it in and out and it should break off easily. Make sure you have a good grip on it...
I got a thought on outboard motor drain plug threads.

You know how aluminum is. It likes to fatigue and fracture. Not a lot of fatigue strength in the stuff. I am guessing that over a number of tightening cycles (maybe to the point of "let's just snug it down a bit more to be sure it does not loosen") the threads simply fatigue to the point that one day they crack and then are prone to letting go.

On another (the wrong) forum the OP said he was using a torque wrench to tighten his plug and it just kept on turning. Apparently with little torque being applied. I have heard this before from Yamaha four stroke owners. That the oil pan threads stripped and they were barely tightening the drain plug.

As a test, some other fools and me set out to intentionally strip the threads on a brand new oil pan. It took a hellava lot of muscle. Much more than any of us fools would have imagined. Actually took a breaker bar to get the job done.

So do you think my fatigue theory holds any water?
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