Thread sizes

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Big Jim
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Re: Thread sizes

Post by Big Jim »

Can someone help me with the thread size of the 2 winged screws on the font stick of the hood frame ?
Thanks

gmbailyes
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Re: Thread sizes

Post by gmbailyes »

Hi, I've just set out on the Morris Minor journey and I'm currently tidying up the engine bay. I noticed when removing the fan that one of the bolts on the timing chain cover was missing. I see from the bolt chart that this could be either a 1/4" or 5/16th bolt. (Great list btw) . I just need a little further guidance as to what exactly to order eg. length etc. I'll buy both just to have some spares. I have a 1967 1098 saloon. Thanks
philthehill
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Re: Thread sizes

Post by philthehill »

The 1/4" UNF screw into the front engine plate - the 5/16" UNF screw into the block.
The BMC part numbers are 1/4" UNF = HZS0403................5/16" UNF = HZS0505.
If you order the above part numbers you will get the right length set screws.
Items No: 51 & 54 in the attached link:-

http://www.moss-europe.co.uk/shop-by-mo ... 0f3d3.html

You will need the spring washers as well.

TvdWerf
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Re: Thread sizes

Post by TvdWerf »

I found some 5/16 NF taps between the BSF , but when I look at it, and tried it in the body, for the wing bolts, it goes by hand...
What is the difference between NF and BSF?
MM '51 LHD sidevalve
philthehill
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Re: Thread sizes

Post by philthehill »

I take it that when you refer to NF you mean UNF.
The 5/16" Unified National Fine (UNF) tap/thread has 24 threads per inch and the 5/16" British Standard Fine (BSF) tap/thread has 22 threads per inch.

TvdWerf
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Re: Thread sizes

Post by TvdWerf »

No, there is for sure NF stamped, not UNF on different taps....
And because the U is missing, and the tap is going by hand in a new 5/16 BSF nut, I wondered about it..
It are old taps ;)
MM '51 LHD sidevalve
philthehill
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Re: Thread sizes

Post by philthehill »

The NF stands for American National Fine (NF)
During the second world war differences in the thread pitch and form caused serious problems especially in engine manufacturing and repair; therefore it was agreed that the pitch would be standardised at 60 degrees and that the root would be round and the tip could be optional either being flat or rounded. The new classification was Unified National Fine (UNF).
There is little difference between 22 and 24 TPI that the tap may well screw in with little effort.

https://sizes.com/tools/thread_ncnf.htm

IslipMinor
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Re: Thread sizes

Post by IslipMinor »

thread size of the 2 winged screws on the font stick
Definitely 5/16" BSF!

On a Minor anything to do with the body, including suspension mounts, was originally BSF or for the small threads BA - I can't think of a BSW thread anywhere, but is there?

Some of the replacement body related parts use UNF or even a metric thread!
Richard


midget
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Re: Thread sizes

Post by midget »

IslipMinor wrote:
thread size of the 2 winged screws on the font stick
Definitely 5/16" BSF!

On a Minor anything to do with the body, including suspension mounts, was originally BSF or for the small threads BA - I can't think of a BSW thread anywhere, but is there?

Some of the replacement body related parts use UNF or even a metric thread!

Lots on the Van Richard.
I had to restock with WW sockets to strip mine.
John
philthehill
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Re: Thread sizes

Post by philthehill »

Original 5/16" body captive nut threads are BSF with the set screws having 1/4" BSW Whitworth heads so the requirement/need for Whitworth spanners/sockets.

Declan_Burns
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Re: Thread sizes

Post by Declan_Burns »

Just to add some more thread info.

I'm pretty sure that the master cylinder filler cap has a 1.1/8" X 20 TPI BS cycle thread.
The blanking plug at the rear is 1" X 20 TPI BS cycle thread. This I can confirm as I sent Tracy Tools a blanking plug to check when I bought the die from them earlier in the year.
The dies are available from Tracy tools.
http://www.tracytools.com/taps-and-dies ... YCLE-PITCH

Regards
Declan


Regards
Declan
TvdWerf
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Re: Thread sizes

Post by TvdWerf »

I should like to have a list of sidevalve bolts and nuts, complete with the torque.
In the manual from the MM, nothing is written about it.
In a post from Mike, I found the head bolts, M10; 44 lb/ft, but the crank shaft bolts are also important.
I think this information should be in the topic "Thread sizes" ;)
MM '51 LHD sidevalve
BTU268F
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Re: Thread sizes

Post by BTU268F »

Hi, can anyone tell me the thread size for the fixings for the floor mounted dipswitch, back of my head I have 2ba but wanted to check before ordering any. Thanks in advance.
les
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Re: Thread sizes

Post by les »

I may be wrong but I'm thinking they were/are self tapping screws.

BTU268F
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Re: Thread sizes

Post by BTU268F »

Yes self tappers to hold the switch to the metal plate, but it's the fixings for the plinth that rests on the floor.
Morris-Minor-1000-High-Low-Foot-Beam.jpg
Morris-Minor-1000-High-Low-Foot-Beam.jpg (16 KiB) Viewed 23362 times
les
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Re: Thread sizes

Post by les »

Ah right. I cant help then, only to suggest 2 ba would be a good bet.

jagnut66
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Re: Thread sizes

Post by jagnut66 »

Hi,
Just seen this and more specifically the list on page 1. Very useful.
Best wishes,
Mike.
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
BTU268F
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Re: Thread sizes

Post by BTU268F »

[quote="les"]Ah right. I cant help then, only to suggest 2 ba would be a good bet.[/quote

Yes 2ba fitted perfectly
IslipMinor
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Re: Thread sizes

Post by IslipMinor »

I have made some updates and additions to the list of bolt/thread sizes, using various sources, including the later posts in this thread.

Also inserted a column for the bolt/screw/stud length as they become available.

Please let me know of any updates that should be included.
Richard


Declan_Burns
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Re: Thread sizes

Post by Declan_Burns »

Here's another strange one.
The filler cap on the top of the front damper.
From my measurements it is certainly 26tpi and measures 7.9mm OD diameter which suggests 5/16".
I doubt if it is BSB which has 26tpi and is 55°.
I am nearly sure it is 5/16 x 26 BS Cycle, 26tpi and 60°.
Can anybody confirm?

Regards
Declan


Regards
Declan
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