Bonnet spare wheel carrier thread

[jpetropoulos]

I am taking a bunch of my galvanized parts for my Series 3 to be regalvanized. I expect that all of the captured nuts will need to be tapped. I have figured out all of the correct thread sizes except for the captured nuts in the spare wheel carrier that sits on the hood. This is the bolt from Rovers North that goes in there. https://www.roversnorth.com/parts/pl...series_iia_iii Does anyone know the thread type> It is close to a typical 1/2" coarse thread but I am sure that it is a unique type. I have seen it referenced as Witworth and BSF. Does anyone know the right thread type so I can get the correct tap?

Thanks in advance

Jack

[TedW]

i am taking a bunch of my galvanized parts for my series 3 to be regalvanized. I expect that all of the captured nuts will need to be tapped. I have figured out all of the correct thread sizes except for the captured nuts in the spare wheel carrier that sits on the hood. This is the bolt from rovers north that goes in there. https://www.roversnorth.com/parts/pl...series_iia_iii does anyone know the thread type> it is close to a typical 1/2" coarse thread but i am sure that it is a unique type. I have seen it referenced as witworth and bsf. Does anyone know the right thread type so i can get the correct tap?

Thanks in advance

jack

1/2" bsf.................

[jpetropoulos]

1/2" bsf.................

Thanks Ted