Screw thread ID help

[Apache]

Guys - my TD5 has a butchered sump plug. Someone has tapped it out much larger than standard and re threaded. They have further bodged it by taking an existing sump type nut - filling off the edges and welding it to a larger nut!

The shank diameter fits slightly loosely in the jaws of a 16mm spanner - and snugly in a 5/8 (15.875mm).

(I cant find my vernier gauge!)

The thread pitch is 1.5, but my tap and die set only goes up to M12

Do I presume this is M16 X 1.5 or some imperial thread?

They have welded a 24mm bolt head on, but not sure that adds much

I was going to fit on of the easy drain plugs - to mean once I get this sealed I never have to disturb it again

Cheers

 

[Sidewinder]

M16x1.5 is a standard thread, it is in fact the 16mm metric conduit thread.

 

[OnOff]

The STANDARD thread on a TD5 should be M16x1.5. It's a finer pitch to offer better sealing than a normal, metal basher's, coarse metric thread which is M16x2. I don't have a 16x1.5 though.....

I can offer the following near sizes if of any use:

M14x2 (coarse)

M16x2 (coarse)

M20x1.5 (electrical)

M20x2.5 (coarse)

M24x3 (coarse)

M25x1.5 (electrical)

All are HSS btw.

 

[ProDave]

My local garage has a drawer full of assorted sump plugs, taps and helicoil inserts so he would sort it in a thrice. Not much help to you I know.