Series 3 Oil Pressure Switch thread

[doobie]

Folks,
Can anyone confirm the thread used on the Oil Pressure switch a Series 3 2 1/4 Petrol engine (3 main bearing). I believe it to be a 3/8" B.S.P. but this is assuming part of the P on my die has worn off as it looks like an "F". The thread looks anything but "fine" but the only other similar thread I can find to try and confirm the size on is a 3/8" 16 BSW tap. Had a search of the internet but not found anything to confirm.

 

[Blackburn]

Not 3/8 bsp.
British Standard Pipe


Nominal Size
(inches) T P I Major Diameter BSP BSPT 3/8 19 0.656 15.25 mm
https://www.newmantools.com/taps/bsp.htm
attached Unipart cross refereence shows thread options you may find it by part number

 

[doobie]

Thanks, it is a 3/8" BSF thread then, its definitely not 15mm diameter!

 

[Blackburn]

Holdens seem to agree with you , https://www.holden.co.uk/displayproduct.asp?pCode=070.027
As does this thread from series 2 forum.
http://www.series2club.co.uk/forum/forum/index.php?topic=96587.0

 

[rob1miles]

3/8 BSF is my bet but are later ones UNF? (That looks too course for UNF)