Rear suspension Nut sizes??

[paulk]

Just ordering the rear shakle pins (4off) and front special pins(2 off) for Milly.

Cannot find and frankly get lost with UNF BSF and the fact that my Whitworth spanner size is either 1/16 bigger or smaller than the nut size I need.

I'm just trying to order the Nuts required and know that the 8 for the shackle pins are 5/16 whitworth spanner size but what size is the nut? is it 3/8bsf? or am I going the wrong way?

Also the Front special pin is a totally different thread ,much finer, is this UNF? and if it is what size?

Please help before my head explodes!

[aupickup]

i beleive the rear shackle nuts are 3/8 bsf, tho not 100% sure

what front special pins are we talking about, if it is the eyebolt pin, then its the same size as the rear shackle pins and nuts

[paulk]

The Pin I mean is the front Shackle pin (the one that has a chunky head with two pin holes in it)

Its definatly a different thread and it matches the Engine mount to engine tower thread
(I just happen to have a new engine rubber mount on the computer table )

[aupickup]

ah yes ok it is the same thread

[paulk]

Ahh yes but what is it?
I think its 3/8 UNF but can't remember what spanner size it was when I took it off?

[bmcecosse]

If 3/8 unf then it will be 9/16" AF spanner. You really need to have a good selection of both UNF and Whit spanners - and of course some replacement parts now have Metric threads !!

[paulk]

The front pin is definatly 9/16" af so I'm assuming thats a 3/8" UNF

Have loads of AF spanners but only a handful of Whitworth
(Birthday pressie list has now been upgraded but must wait a few months)
Having said that I have not found myself wanting for whitworth since stripping and rebuilding milly.

Have been quite surprised how many more fixings on the 1959 Minor are Whitworth than our previous 1969 Minor, They must have really started to faze out the older bolts.

[Alec]

Hello Paul,

I don't think that there was any difference between early and late models. Most body fasteners were Whitworth threads and the mechanical part (engine\gearbox etc were unified (American threads)

As a matter of interest, and I agree it is confusing, Whitworth spanners are marked as BSF being 1\16" smaller than BSW but they are not. What happened is that during the war (WW2) to save metal the hexagons of fasteners were reduced by one fastener size, namely 1\16" so a 3\8" Whitworth (Bolt diameter remember) now had the hexagon of the next size down i.e, 5\16" This is now true whether it is coarse or fine, (BSW or BSF).

Alec

[Packedup]

I've found 15mm and 16mm metric sockets have a habit of fitting the more obscure sizes on Minor suspension pretty well. The rear shackles and U bolt nuts tend to be one or the other, and whatever isn't generally works OK with a 9/16 AF

[Alec]

Hello Packed up,

while there are one or two sizes that metric tools can be used, e.g. 7\16AF and 11mm it is much more desirable to use the correct size. The problem with a slightly loose fit is when it comes to loosening very tight fasteners is that they can slip, which at best damages the hexagon making it harder to remove and the possible danger to the user.

Alec

[Packedup]

I agree, but 16mm/ 5/8" AF seems to fit very nicely on some of the fasteners, and 15mm is perfect for others. I don't worry about what the threads are, as it seems different replacement parts come with different fasteners - The fitting kit for saloon rear springs I had even had the same thread but different head sizes on some of the U bolts!

[alex_holden]

Why not just use the correct size? It's not like Whitworth sockets and spanners are incredibly rare and expensive.

[chickenjohn]

Why not just use the correct size? It's not like Whitworth sockets and spanners are incredibly rare and expensive.

I agree, get a set of Whitworth sockets and spanners, the Minor suppliers sell a set of Whit sockets on a rail for under £20 and spanners can be picked up on Ebay/ autojumble/ folk here for not very much money. Ask any elderly relatives or neigbours if they have any they no longer need, my Dad gave me his old Whitworth spanners and I have used these a lot on my Minors.

Its amazing how much easier these nuts and bolts are to undo if you have the right size tools rather than trying to make do with metric or AF for Whitworth sized heads. Been there, done that, rounded nuts, skinned knuckles, swore somewhat and bought the Whitworth tools.