Thread sizes

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midget
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Re: Thread sizes

Post by midget »

Any one know the thread for thermostat housing STUD into head please. I have exhausted my limited range of taps/dies and it is not a common one. I am guessing 5/16 UNC?
John
philthehill
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Re: Thread sizes

Post by philthehill »

The thermostat housing studs are 5/16" x 18 TPI UNC into the head and 5/16" x 24 TPI UNF for the nut.

midget
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Re: Thread sizes

Post by midget »

Thanks Phil.
John
pgp001
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Re: Thread sizes

Post by pgp001 »

Hi

Does anyone know what size the two nuts are inside the door under the quarter light please. It looks like I might need to get a deep socket as there is a lot of thread sticking through the nuts.

Thanks
Phil
jagnut66
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Re: Thread sizes

Post by jagnut66 »

Hi,
As this post is now on its 6th page, perhaps what we really need is a chart, which any member can access, download and print off, listing thread sizes and where they were originally applicable on the Minor, from the 1948 MM through to the last Minor 1000.
Does someone on here have the knowledge and time to do this?
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.....)
IslipMinor
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Re: Thread sizes

Post by IslipMinor »

Mike,

The complete chart (excl the MM SV) is on Page 1 of this post, which I used to update as new information became available, but with the new (unnecessary imo) restrictions on editing after a few hours, that is no longer possible.

Mods, Could we start a 'sticky' with just the table and ideally be able to update it as I could before? If we do use a sticky, then it would be a good opportunity to get input from as many sources as possible to ensure it is as complete as it can be. I maintained it before, and am happy to do so again, just need to be able to edit!
Richard


jagnut66
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Re: Thread sizes

Post by jagnut66 »

The complete chart (excl the MM SV) is on Page 1 of this post
Very useful, sorry I missed that, it does warrant a post (or even section) of its own.
but with the new (unnecessary imo) restrictions on editing after a few hours, that is no longer possible.
I thought that had changed, as I have tried to add to some of my posts in the recent past but have ended up starting anew each time.
So why has this changed?
I have to say that I agree with 'Islipminor', in that it wasn't necessary.
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.....)
pgp001
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Re: Thread sizes

Post by pgp001 »

My question seems to have been bypassed :D

Does anyone know what size the two nuts are inside the door under the quarter light please. It looks like I might need to get a deep socket as there is a lot of thread sticking through the nuts.

Thanks
Phil
win
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Re: Thread sizes

Post by win »

Here is a list of spanner sizes I have had hung up in my garage for many many years, no guarantees on accuracy, but a good start.
Regards Win

BIG ENDS 9/16 AF GEARBOX TO ENGINE BOLTS ½ AF
BLEED NIPPLES 7/16 AF H/D ADJUSTMENT NUTS 5/16 WHIT
Bonnet & Boot Hinges 3/16WHIT HOCKEY STICK NUTS 3/16 WHIT OR 4 BA
BRAKE BACK PLATES ½ AF HOSE CLIPS 9/32 AF, 7mm
BRAKE PIPE UNION 3/16 WHIT LOWER ARM BOLT 5/16 WHIT
Bumper Blade to Valance 1/4WHIT LOWER TRUNNION NUTS 9/ 16 OR ½ AF
BUMPER NUTS 7/16 WHIT M/C FILLER 7/16 WHIT
CLUTCH ADJUSTMENT ½ AF AND 5/8 AF MAIN BEARINGS 5/8 AF
CLUTCH COVER BOLTS ½ AF MANIFOLD TO HEAD NUTS ½ AF
CYLINDER HEAD NUTS 9/16 AF OIL FILTER PIPE ¾ AF
Diff Pinion Nut 1,1/8 AF OIL FILTER STUD NUTS 9/16AF
DIFFERENTIAL TO BANJO CASING ½ AF RACK ARM TO TRACK ROD END 3/8 WHIT
DISTRIBUTOR CLAMP BOLTS 7/16 AF RADIATOR BOLTS ¼ WHIT
DITTO BOTTOM 9/16 AF REAR BANJO BOLTS 5/16 WHIT
DOOR TO A POST ¼ WHIT Rear Hub Nut 1,1/8W or 1,7.8 AF
DYNAMO /FANBELT ADJUST TOP ½ AF ROCKER COVER 5/8 AF
ENGINE MOUNTING NUTS ½ AF ROCKER PEDASTAL NUTS ½ AF
engine mounting bolts 1/4 Whit SIDE COVER BOLTS ½ AF
ENGINE PLATE BOLTS ½ AF STARTER DOG ¾ WHIT LONG SOCKET
EXTENSION BOLTS 7/16 AF STARTER MOTOR MOUNTS 9/16 AF
Eye Bolt 1/2WHIT STEERING WHEEL NUT ¾ WHIT
EYEBOLT PIVOT 9/16 AF SUMP BOLTS 7/16 AF
FAN BOLTS 7/16 AF SUMP PLUG ¾ AF
FILLER AND DRAIN PLUGS 3/8 WHIT Tappet adj nut 7/16AF
FLEXIBLE HOSE NUT 3/8 WHIT THERMOSTAT HOUSING NUTS ½ AF
FLYWHEEL BOLTS 9/16 AF TIE ROD TO CHASSIS 5/16 WHIT
FORK NUT 3/8 WHIT TIE ROD TO FORK NUT & BOLT ¼ WHIT
FRONT HUB NUT 15/16 AF TIMING CHAIN COVER 716 AF AND ½ AF
Front Panel lower 3/16WHIT TOP TRUNNION FULCRUM PIN NUTS 7/16
Front Panel top 1/4WHIT UJ BOLTS AND NUTS ¼ WHIT
FRONT WINGS ¼ WHIT WATER PUMP NUTS ½ AF
GEARBOX COVER PLATE NO 3 PHILLIPS WHEEL NUTS 3/8 WHIT
GEARBOX SIDE COVER NUTS 7/16 AF WINDOW ASSEMBLY 3/16 WHIT
Image
South Yorkshire
pgp001
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Re: Thread sizes

Post by pgp001 »

pgp001 wrote: Mon Feb 03, 2020 1:53 pm My question seems to have been bypassed :D

Does anyone know what size the two nuts are inside the door under the quarter light please. It looks like I might need to get a deep socket as there is a lot of thread sticking through the nuts.

Thanks
Phil
Just a quick update.
The nuts in question are 7/16 AF, as are the ones holding the window frame vertical members into the door.
A tubular box spanner was the tool I used for dismantling these.

Phil
win
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Re: Thread sizes

Post by win »

O dear
when I posted this it was in 2 separate columns sorry.

Regards Win
Image
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don58van
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Re: Thread sizes

Post by don58van »

Does anyone know the thread specification of --

the studs/nuts of the chrome facia side-pieces on the dashboard of 63 onward Minors?

I have a feeling that it is a BA specification.

Looking forward to hearing from someone who knows.

Don
don58van
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Re: Thread sizes

Post by don58van »

I am now able to answer my own question.

It is #6-32 UNC.

I bought some on-line and can confirm that they fitted perfectly. :D

I hope this might be useful to others who are dealing with missing studs and/or nuts (as I was).

Don
IslipMinor
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Re: Thread sizes

Post by IslipMinor »

Don,

I cannot say for certain, as ours is 1958, so does not have the dash surround, but it is unlikely that a Unified thread was used originally on the body. There was usually a clear distinction between thread series and application. The body uses the BSF/BSW series, and mechanical uses UNF/UNC. If you look at the lower front suspension arm, the chassis/body end uses BSF threads and the outer end where it meets the upright is UNF. Another example is the front engine mounting tower - the rubber mount is UNF and the tower to floor pan bolts are BSF.

The outside diameter of a 4BA thread (0.1417”) is slightly larger than a #6-32 UNC (0.138”).

Aftermarket parts quite often use a different thread to the original, particularly when the original thread was BSF or BA, and #6-32 could be easier to source than 4BA these days.
Richard


RobThomas
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Re: Thread sizes

Post by RobThomas »

Plug in the back of the Lockheed master cylinder where a stub can be fitted for a remote reservoir. It is 1 inch x 20 tpi, UNEF. Same thread as pop-off valve on the Shorrocks supercharger. On page one it says BSC but I'm somewhat doubtful of this since 1 BSC is 26 tpi.
Cardiff, UK
philthehill
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Re: Thread sizes

Post by philthehill »

Rob
BSC is not just 26 TPI
See:-
https://britishfasteners.com/threads/bsc.html
https://britishfasteners.com/threads/cei.html
I had an interesting one last Friday, vintage Douglas motorcycle which has an internal band brake. The screws holding the band to the drum were 3/16" x 28 TPI. I have a comprehensive range of taps, dies and thread gauges and the nearest I could get to the thread/size was BSC(BSCY). Tracy Tools lists the 3/16" BSCY threads as 20, 24, 26, 28, 30 & 36 TPI.
To get round the problem new bolts will most likely be made using a 3/16" BSCY die.

Phil

GavinL
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Re: Thread sizes

Post by GavinL »

Assume it was 60° thread form?
jeff-d
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Re: Thread sizes

Post by jeff-d »

a new one for the pinion & bush speedometer drive housing the size is 1.1/8inch nut
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