correct thread size

[BRI MK1]

can anybody tell me the original thread size for mk1 mini nipple surround brackets as i think i have been sent the wrong screws but the company say they are the the correct ones, they sent me 1/4 unf i think this is wrong cheers brian.

[Andrew1967]

The fixings are 1/4 unf cross head threaded screws similar to the door hinge screws.

That's what they are in my 1960 with original sills.

[morris cooper]

I've usually found one 10/32 or 3/16 unf set screw in the vertical fixing and one no10 self tapper in the lower fixing on original cars.

[66S]

I've usually found one 10/32 or 3/16 unf set screw in the vertical fixing and one no10 self tapper in the lower fixing on original cars.

Correct, they were not 1/4" UNF originally.

Al

[Andrew1967]

I've usually found one 10/32 or 3/16 unf set screw in the vertical fixing and one no10 self tapper in the lower fixing on original cars.

Correct, they were not 1/4" UNF originally.

Al

Interesting Al.

Maybe earlier cars were different ?

Just been out to the garage and both screws are 1/4 UNF on each side.

[66S]

Hi Andrew,
I suspect they might have been enlarged to 1/4" by someone. I don't have a parts book here at work but that would confirm it.

I haven't heard from you in a while, busy or are e-mails not getting through?

Al

[Andrew1967]

Hi Al,

I don't think that's the case but could not rule it out. The 850 was very original body wise and the old screws were still in place. But who knows. I'll check out my early parts book.

Better answer your email now

Andrew

[BRI MK1]

Thankyou for your comments all the cars ive had have been 3/16 unf,its just the lady at somerford got very stroppy about this and told me i was wrong, i checked two of my other cars today that are original and they are 3/16th cheers brian.

[66S]

I don't think that's the case but could not rule it out. The 850 was very original body wise and the old screws were still in place. But who knows. I'll check out my early parts book. Andrew

Hi Andrew

I now recall you, me and others discussing this issue some time ago on a forum, maybe the MCR ?? Trouble is, I cannot recall what we finally came up with

All five ( '63, 2 x '64, '65 and '66) of my Mk 1's have the smaller screws.

Al

[Andrew1967]

I don't think that's the case but could not rule it out. The 850 was very original body wise and the old screws were still in place. But who knows. I'll check out my early parts book. Andrew

Hi Andrew

I now recall you, me and others discussing this issue some time ago on a forum, maybe the MCR ?? Trouble is, I cannot recall what we finally came up with

All five ( '63, 2 x '64, '65 and '66) of my Mk 1's have the smaller screws.

Al

Thats quite probable Al, I forgot about that.

Five.......theres no hope is there Al ?

[herlufsholm]

All Mk1 Minis should have 1/4 " UNF crosshead screws to fasten the rear radius arm shroud.
According to early parts list AKD1153 and later AKD3502, it has the same partnumber PMZ0408.
All Mk1 Minis I have seen, when repairing sills and subframe mounts, has 1/4" UNF nuts fastened to the subframe mounting.
I have also seen many unauthorised repairs with selftapping screws and so on, because the screws were prone to break, when tried undone.

Regards Michael

[Andrew1967]

Thanks Michael, an ally in my camp

I've just checked my parts manual AKD1153 and it shows both fixings as 1/4 UNF x 5/8 Phillips head screws PMZ0408

Al, I found that MCR thread from 2010 by Googling PMZ0408 and I noted that my Mk2 parts manual showed one set screw and one sheet metal screw for each shroud.

Looks like the 1/4 UNF bolts were superseded by less substantial fixings sometime during Mk1 production. My parts book is dated 6/61.