Thread sizes

Discuss mechanical problems here.
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Thread sizes

Post by philthehill »

Just an update on the thread for the starter dog/crankshaft pulley bolt.
The thread is 5/8" x 16 TPI UNS (Unified National Special) with 55 degree Whitworth Thread Form.
I have now managed to get hold of one of these special taps off 'e' bay and can confirm the above is correct.
The tap usually costs in the region of £70 - £100 pounds so I am well pleased with my purchase which was considerably less.
If you try a 5/8" x 16 TPI UN(F) or similar you will ruin the threads.

SUE482
Minor Fan
Posts: 291
Joined: Mon Aug 09, 2010 11:20 pm
Location: In the Middle
MMOC Member: Yes

Re: Thread sizes

Post by SUE482 »

Under Gearbox, what are the: "Remote Control to Gearbox Bolts"
"Remote Housing to Bottom Plate Bolts"
I know that the "Gearbox Extension to Gearbox is 1/4" UNF all 9 of them.
Ian
Should be ready for tea time.
minortech
Minor Friendly
Posts: 12
Joined: Wed Oct 25, 2006 11:10 pm
Location: Glasgow
MMOC Member: No

Re: Thread sizes

Post by minortech »

I am having a problem with the thread size of the drop link mounting pin on the rear chassis leg. It's really only a problem as I am trying to fit a Spax CK10 Conversion Kit which involves fitting a modified mounting pin over the original pin. The Spax pin has a ⅜“BSF thread which I believe is what that the chassis pins should be. However, both of the chassis pins on my car appear to be 5/16" BSF so the Spax pins won't fit. Has anyone else come across this different thread size? The rear chassis legs were replaced about 20 years ago.
minortech
Minor Friendly
Posts: 12
Joined: Wed Oct 25, 2006 11:10 pm
Location: Glasgow
MMOC Member: No

Re: Thread sizes

Post by minortech »

I have been advised that in the 90s Henrics supplied the rear chassis repair panels with a 5/16" thread on the mounting pin. Reason unknown.
Hunsta
Minor Friendly
Posts: 37
Joined: Wed Jul 30, 2014 11:33 am
Location: Gympie Qld
MMOC Member: No

Re: Thread sizes

Post by Hunsta »

bmcecosse wrote:Which thread do you need to know...?
If we're asking questions. Can you tell me what bolt size and thread are for the bolts that screw into the gearbox for the gearbox mounts on the later model 1000's. I believe they are a course thread UNF.
Cheers
Craig
les
Minor Maniac
Posts: 8737
Joined: Tue Feb 12, 2002 12:00 am
Location: kent
MMOC Member: Yes

Re: Thread sizes

Post by les »

Unf = fine. Unc = coarse. The bolts are 5/16 Unc.

Hunsta
Minor Friendly
Posts: 37
Joined: Wed Jul 30, 2014 11:33 am
Location: Gympie Qld
MMOC Member: No

Re: Thread sizes

Post by Hunsta »

les wrote:Unf = fine. Unc = coarse. The bolts are 5/16 Unc.
Cheers
RobThomas
Minor Legend
Posts: 2646
Joined: Thu May 11, 2006 10:34 am
Location: Cardiff
MMOC Member: Yes

Re: Thread sizes

Post by RobThomas »

Since 2BA threads are getting harder to come by I found that 10-32 UNF is a close substitute.
2BA is 0.180 and about 31 turns per inch
10-32 is 0.190 and 32 truns.

These hold the burst latches onto the B-posts, the bonnet buffers, the hood pivots on Convertibles, the ignition switches on MMs etc etc. Called "Oval head" or raised-countersunk.

Number 6 screws are the size used for the chassis data plate on MMs. Order as a Pozidrive pan head Number 6 (9mm or 3/8 length) for the nearest equivalent.
Cardiff, UK
Herrybraun
Newbie
Posts: 1
Joined: Tue Feb 23, 2016 10:59 am
Location: Leeds
MMOC Member: No

Re: Thread sizes

Post by Herrybraun »

There are really some reply which describing size in detail. I love this discussion.
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Thread sizes

Post by philthehill »

Rob
If you are having trouble getting BA fastenings you should try:-

http://www.gwr-fasteners.co.uk/ba-fasteners-1-c.asp

I use them all time for various nut/bolts/etc; and they are good for small quantities.
Quick delivery too! :D
Phil

GerhswinLong
Newbie
Posts: 4
Joined: Thu Apr 14, 2016 2:09 pm
MMOC Member: No

Re: Thread sizes

Post by GerhswinLong »

Good day guys

Thanks so much the the useful information provided. I am in the process of restoring an old Morris Minor and am in need for LOTS of nuts and bolts. The list given earlier in the thread seems handy but does anyone have an idea of the length of the bolts?

I need the length in order to order these as well.

Any assistance is welcome :D

Regards
Gershwin
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Thread sizes

Post by philthehill »

Gershwip
If you order the bolts / nuts required from the usual suppliers against the parts numbers posted on those suppliers web sites the bolts and nuts will come in the correct sizes / lengths.
If you wish to purchase from a non normal supplier please identify what you require and we will be pleased to help.
Phil

GerhswinLong
Newbie
Posts: 4
Joined: Thu Apr 14, 2016 2:09 pm
MMOC Member: No

Re: Thread sizes

Post by GerhswinLong »

philthehill wrote:Gershwip
If you order the bolts / nuts required from the usual suppliers against the parts numbers posted on those suppliers web sites the bolts and nuts will come in the correct sizes / lengths.
If you wish to purchase from a non normal supplier please identify what you require and we will be pleased to help.
Phil
Thanks Phil. I am purchasing from a non normal supplier (am based in South Africa). Essentially I need to determine what lengths the bolts are in order for the supplier to assist. The pictures posted earlier givens thread does not give lengths. The list states as example "Gearbox Cover Plate Screws" with specs "1/4 BSF" but not length provided.

Kind regards
Gershwin
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Thread sizes

Post by philthehill »

Those particular screws are brass - Philips cross headed (with a semi domed head) - countersunk - 1/4" BSF x 20mm overall length and 26mm overall length where they fit through both the floor and gearbox cross member.
If you post on here your requirements I or other members of the forum will endeavor to help.
Phil

GerhswinLong
Newbie
Posts: 4
Joined: Thu Apr 14, 2016 2:09 pm
MMOC Member: No

Re: Thread sizes

Post by GerhswinLong »

Hi again Phil, here is the list required (essentially I need all bolts and screws required to assemble).[frame]Image[/frame]
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Thread sizes

Post by philthehill »

As a first off reply:-

All nuts except the steering wheel nut are standard. The steering wheel nut (Pt No: ACH6001) is a one off and will have to be supplied by a Minor Spares supplier unless you can get a good S/H one.

Radiator bolts length 1" and trim to length. Make sure that when fitted they do not foul the radiator core.
Kick plate bolts 1 1/4" and trim to length.
Door to 'A 'post bolts/screws are specials (Pt Nos: AJD4547Z (screw) & AAA1498 (bolt)) and will need to be obtained from a Minor spares supplier.
Front wing bolts are 1" long.
Engine tower bolts are 1" long.
Front seat bolts 1 1/2".
Phil

John Naylor
Minor Fan
Posts: 301
Joined: Tue Dec 31, 2013 4:19 pm
Location: WHITSTABLE KENT
MMOC Member: No

Re: Thread sizes

Post by John Naylor »

Just a thank you for all involved in creating these lists, they are brilliant! I printed and laminated A4 copies and have them fixed to the wall of my workshop. I keep my AF and Whitworth/BSF spanners in separate boxes and am quite a 'smarty-pants' selecting the correct spanner first time!

Bertie.
GerhswinLong
Newbie
Posts: 4
Joined: Thu Apr 14, 2016 2:09 pm
MMOC Member: No

Re: Thread sizes

Post by GerhswinLong »

Thanks again Phil.

John, I will post more details as I stumble across them during the assembly process
bmcecosse
Minor Maniac
Posts: 46561
Joined: Wed Feb 16, 2005 11:24 pm
Location: ML9
MMOC Member: No

Re: Thread sizes

Post by bmcecosse »

Where it is a 'nut and bolt' situation - and especially since you are in SA - I see no reason not to use equivalent/easily obtainable Metric nuts and bolts. Some of the replacement parts supplied from the UK now come with Metric studs/nuts etc anyway. Just beware the 'stainless steel' kits offered by some suppliers - partly because they may not be very 'strong' and mostly because stainless against mild steel creates a 'cell' when damp - and the mild steel around the fixing rots away.... :roll:
ImageImage
Image
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Thread sizes

Post by philthehill »

Unfortunately many of the bolt dimensions required mate into captive BSF threads i.e. door/A post, wing bolts and seat bolts.
Where it is a completely free standing (not fitted) nut and bolt - yes by all means use a metric nut/bolt. Aim for at least 8.8 grade and as above do not use stainless for the reasons quoted.
Phil

Post Reply