Bonnet and boot stud threads

[southerly95]

Could someone remind me what type of thread and size the studs are on boot and bonnet hinges please, gracias, John

[aupickup]

poss 7/16 af i think off hand

[bmcecosse]

7/16" AF heads on the bolts - but 1/4" UNF is the thread.

[aupickup]

[mike.perry]

There are two stud sizes.
The large stud which holds the hinge to the body has a pitch of 22 TPI = 5/16 UNF with a nut size of 1/2 A/F.
The small studs which attach to the boot and bonnet have a pitch of 28 TPI = 7/32 UNF with a nut size of 7/16 A/F
I think I read the chart correctly

[bmcecosse]

Pretty sure mine are 1/4" UNF -with 7/16" heads. A bolt of 5/16" thread would normally have a 1/2" AF head! Perhaps early cars were different ?

[mike.perry]

The two large studs have got 1/2 A/F nuts

[bmcecosse]

Hmm - I'm not aware of 'large studs' - will have a look at my spares tomorrow!