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That was the tap I ordered (Hansen brand) and what is says on its side ............ but it appears to be too large ????????? Frustrating.
 

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Dunno. Seems like mine was a snug fit. Or am I remembering the diff, not the trans? Would they be different?
Andrew
 

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Hoping some folks don't mind revisiting this subject. . .

On my 101 tranny the drain plug hole has some buggered threads. To fix the threads I ordered a M22x1.5 tap. When I measured the tap OD the measurement gave 22.2mm. I've measured a couple of drain plugs and measurements cluster around 21.8


The guy at the industrial tool/fastener shop thought the plug and hole might be some obscure European/British straight pipe thread.


I definitely don't want to tap the hole only to discover I've made the problem worse. Any thoughts or comments are appreciated!!!


Chuck
 

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The SEAL is made by compressing the seal washer (so you don't need to worry about thread leaks), and a tap must be larger than the thread of the intended 'bolt' by a bit - but 0.4 mm sounds way to much! The thread valley to peak of a 1.5mm pitch screw is about 1.3 mm (by this site - https://en.wikipedia.org/wiki/ISO_metric_screw_thread), so that 0.2mm play (each side) is about 1/6th of the thread.

Sounds like it might work, but be very loose!!


Say - did you measure your drain hole?? it should be bigger than the plug's thread diameter minus 2.6 mm by some amount. If that amount bigger is 0.4 mm then you are good to go...
 

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Thanks. Yeah, that's exactly what I'm worried about. I'd hate to rip out the threads before I can torque enough to seal the washer.

I'm my perfect world a couple folks would chime in that they'd tapped the hole to M22x1.5 and used drain plugs w/ OD's similar to mine and had no problems.
 

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Thought I'd close the loop. Silly me for questioning the earlier posters.

I drilled and tapped a piece of scrap w/ the 22x1.5 tap. Plug fits. Little more slop than ideal but I think quite acceptable.
When chasing the threads on the tranny case could definitely feel the section of damaged thread.

Thanks to those that helped!
 
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