Thread size carb stud

[38rover]

I need to helicoil the stud that holds the carb down anybody know the size it should be UNC 5/16 or 3/8 I would guess saves me stripping down twice

[thebadleys]

ROM states 5/16 UNC Torque 15 - 20 lb ft.

Nigel

[GDPR]

the stud in the manifold the pedestal sits on is 3/8" unc in the manifold.....

[thebadleys]

Wrong Again

[38rover]

Thank you for those two answers but you can understand why I am confused
I have now checked my ROM should have done that first and the stud I think is carb to adaptor is 5/16 UNC UNF
carb adaptor adjustment is 3/8 UNF since it is a stud the non nut end should be UNC so my money is now on 5/16 UNF?

[GDPR]

Wrong Again

Not wrong at all Nige, just I wasn't certain which stud was being referred to so thought I'd give the other option - it's pretty rare for the pedestal carb stud to strip, whereas the manifold/pedestal regularly gets cattled

[V Mad]

The thread at the bottom of the stud where it screws into the manifold is 3/8 UNC. I know because I regularly buy bolts to fit into the manifold.

[stag8manod]

Tapped holes into alloy should always be UNC. If it is UNF and you are intending to Heli-coil I would recommend it's changed to UNC.
Cheers Ian A

[38rover]

Tapped holes into alloy should always be UNC. If it is UNF and you are intending to Heli-coil I would recommend it's changed to UNC.
Cheers Ian A

As said it should always be a course thread into a tapped hole in this case UNC 5/16