Whitworth wrenches.... and line/flare wrenches

[VolvoRyan]

Here's one for UK/European friends:

A friend of mine (retired mechanical engineer), who is a 1980's Volvo (VW) diesel nut and rebuilder of SU carbs, discovered that the hydraulic lines on Volvo CAM steering racks are a Whitworth size. Can you still get Whitworth wrenches?

Unfortunately, clearance prevents using anything adjustable in most places, so the Vice-Grip flare wrench tool only gets one so far. The fittings might as well be unobtanium, so more destructive means are out. Despite the cars being 40 years old now, this is a relatively new problem. Rebuilt steering racks were a dime a dozen for decades. Now it's pretty hard to get a rack that works out of the box. I'm playing my own game of rebuilt racks leaking out of the box.

Any thoughts/help?

Thanks!

-Ryan

 

[Dave455]

Hi Ryan,

Yes, Whitworth are no problem.

You will find them made by Snap On, King ****, Gedore, and Elora, to name a few.

I very much doubt that the fittings are unobtanium. They are probably ‘BSP’ (British Standard Pipe), and although BSW and BSF are obsolescent for nuts and bolts, BSP are a common standard.

BSP are used in the U.K. and they are common in Europe too. Worldwide they are probably the most common pipe thread, probably more so than Unified pipe threads, which are rare outside the U.S. or certain industries (oil).

The tools you really need for BSP hydraulic systems are Whitworth flare nut wtenches, and they are slightly more rare. The best were made by Britool, and Blue Point (pre Snap On), but the only option is used!

Edit - The Britool look like this


And the Blue Point like this

 

[Pinemarten]

I found this.........

BRITOOL WHITWORTH FLARE NUT SPANNER 9/16 X 5/8W - £16.99 : The Vintage Tool Company , We sell Tools and Toolkits for Veteran, Vintage, Classic Motor Cars, Motorcycles and Commercial Vehicles

The Vintage Tool Company BRITOOL WHITWORTH FLARE NUT SPANNER 9/16 X 5/8W - in good usedcondition, no owners marks or damageMade in EnglandPart number 4328Sizes are 9/16 and 5/8 inch Whitworth

thevintagetoolco.com

I'm not sure what sizes you need.

 

[Pinemarten]

Ebay UK might be the bast source............

Britool Flare Nut Spanner 4315 Vintage 3/8w x 7/16 W England | eBay

Used Britool Spanner as seen.

www.ebay.co.uk

and this:

Vintage Britool Flare Nut Spanner/Wrench Z4246 3/4 W | eBay

<p>For sale is a vintage Britool Flare Nut Spanner/Wrench Z4246, perfect for all your specialty SAE needs. This single item is made by a trusted brand and has a size of 3/4in. The drive type is also specialty and it comes as a standalone piece, rather than part of a set. </p><br /><p>This...

www.ebay.co.uk

 

[VolvoRyan]

Thanks very much to both of you!

Looks like the size needed is a 3/16W. Calling wrenches by their proper names (spanners!) seems to open up quite a bit more hits on the interwebs!

Thanks again.

-Ryan

 

[Dave455]

Thanks very much to both of you!

Looks like the size needed is a 3/16W. Calling wrenches by their proper names (spanners!) seems to open up quite a bit more hits on the interwebs!

Thanks again.

-Ryan

Some part numbers. Snap On are the best quality, Elora probably the best quality to price ratio.

King ****


Elora

Gedore


Snap On - note they only give the BS size, so a 3/16 BSW is a 1/4 BSF. (Since the war all nuts use one “BS” size).

 

[Pinemarten]

Here is a link to a Continental Hydraulic Fitting PDF. This has tons of information on all types of hydraulic fittings, type of threads etc.......

https://sircoindustrialerie.com/pdf/thread-types.pdf

 

[DonovanSpeed]

If there’s a British motorcycle shop near you they will likely be able to point you in the right direction for fittings if you end up needing them. Like others said there should be stuff available online but sometimes it’s better to talk to someone knowledgeable.

The oil fittings on Triumphs and BSAs might be the same.

 

[rust in the eye]

3/16w? on a hydraulic line? Are you sure?
I stand to be corrected but doesn't a given Whitworth dimension indicate the width of a single flat on the hex head? Is so that would be a very small hydraulic fitting.
Anyway 3/16W is very close to 11mm & 7/16"

 

[VolvoRyan]

3/16w? on a hydraulic line? Are you sure?
I stand to be corrected but doesn't a given Whitworth dimension indicate the width of a single flat on the hex head? Is so that would be a very small hydraulic fitting.
Anyway 3/16W is very close to 11mm & 7/16"

It's on a PS rack, and indeed pretty small, and super close to 11mm and 7/16.... neither of which worked. My friend is the type to pull out the machinist tools and measure things down to the thou.... which is how he determined it was a Whitworth size.

-Ryan

 

[Dave455]

3/16w? on a hydraulic line? Are you sure?
I stand to be corrected but doesn't a given Whitworth dimension indicate the width of a single flat on the hex head? Is so that would be a very small hydraulic fitting.
Anyway 3/16W is very close to 11mm & 7/16"

Firstly - Yes!

BSP pipe fittings use Whitworth wrench sizes as standard.

The size of an original / BSW nut or bolt head is twice the bolt size, ACROSS THE POINTS of the bolt head. If you work out the geometry, it means that a BSW hex is always 1.67 (or somesuch) x the bolt size, measured across the flats.

In practice, BSF threads use one hex size smaller, and since the war BSW use the same.

On BSP threads everything is related to the pipe size, so if you get a 1/8 BSP that’s a fitting for a 1/8 pipe. The thread size will be greater (you can look that up) and the hex size / wrench size greater again.

The “ideal” hex size was then rounded up to the nearest “standard” Whitworth size.

 

[drtyler]

It's on a PS rack, and indeed pretty small, and super close to 11mm and 7/16.... neither of which worked. My friend is the type to pull out the machinist tools and measure things down to the thou.... which is how he determined it was a Whitworth size.

-Ryan

I needed the same size for a clutch hydraulic line on an MG last year. Ended up with King **** combo from Moss Motors, and it worked well. Since the open end fit properly, it was no issue.

7/16 and 11mm would not work.

 

[matthew]

British Stanard Pipe being used on a hydraulic line makes some sense. Whitworth head on a BSP fitting makes some sense. The weird part would be the tools for that disappearing earlier than the fittings quit being made. And for that matter a BSP fitting in automotive use from that era without the head having been made metric (or at least AF measurement). At least seems odd to my unknowing eyes…

Flarenut wrench wouldn’t be easy to file to fit, either…

 

[Pinemarten]

What is the line size for the fittings? If it is indeed a 1/8 Whitworth, all the specs are on page 27 of this PDF:

https://sircoindustrialerie.com/pdf/thread-types.pdf

A small fitting like that could probably be disassembled with a regular 3/16 Whitworth wrench. You could also make a "field expedient" crowfoot from the box end of a 3/16 W combo wrench.

 

[Dave455]

British Stanard Pipe being used on a hydraulic line makes some sense. Whitworth head on a BSP fitting makes some sense. The weird part would be the tools for that disappearing earlier than the fittings quit being made. And for that matter a BSP fitting in automotive use from that era without the head having been made metric (or at least AF measurement). At least seems odd to my unknowing eyes…

Flarenut wrench wouldn’t be easy to file to fit, either…

I don’t think the tools are disappearing.

It may even be the continuing demand for tools for pipe fittings that are keeping them alive!

I think this might be one of those cases where you get a slightly different perspective if you are in the U.S. which is probably the biggest country that doesn’t generally use BSP.

In my shop all my air fittings are BSP, all the air chuck fittings on my lathe, all the coolant pipes on the same machine, all the coolant pipes on my Swedish mill, my water hose fittings etc etc. Makes life easy.

If I go out to buy new fittings, they are the same. Haven’t changed all the time I’ve been on the planet, though you can find BSP fittings with metric hex sizes if you want (generally European made),

It is a bit odd, if I work on a vehicle, and use SAE wrenches for the fasteners, and BS for the pipework, but I’m used to it!

Yes, shame the Whit flare nut wrenches are discontinued, but so many folks use adjustables, or even a pliers wrench, on pipe fittings that they probably don’t notice.

 

[Pinemarten]

There are some Whitworth combination wrench sets in tool roll, on Ebay for around $42 shipped.

 

[lolaetype]

With all this talk about British Standard Pipe (BSP) threads maybe it's useful to point out there are two types: British Standard Pipe Tapered (BSPT) in which the threads are tapered similar to, but not interchangeable with, NPT. The other type is British Standard Pipe Parallel (BSPP), in which the threads are not tapered, they are parallel like the threads on a bolt. BSPP fittings require a sealing washer, typically copper.

Both types will take the same wrenches though.

 

[matthew]

I don’t think the tools are disappearing.

As you said after, it’s the flarenut tools for line fittings I was referring to. Cutting a box end is nowhere near as strong. Regular open end doesn’t always cut it…

I don’t know how a Volvo mechanic would feel about it, but I have to imagine there’s a lot of Swedes lacking a set of BSW wrenches, never mind flares…

 

[Dave455]

As you said after, it’s the flarenut tools for line fittings I was referring to. Cutting a box end is nowhere near as strong. Regular open end doesn’t always cut it…

I don’t know how a Volvo mechanic would feel about it, but I have to imagine there’s a lot of Swedes lacking a set of BSW wrenches, never mind flares…

Yes, it’s a shame they are hard to find, they are superb to use, though the Britool ones were always expensive new.

I don’t know if any other manufacturers ever made these. Some must have done.

There was a Swedish thread standard that used Whitworth threads with metric bolt heads. This actually makes a lot of sense, very typical of the practical Swedes, but confused me when I first found it.

I buy those Whit flare nut wrenches when I see them, unless it’s a size I already have multiples of. Strangely, two of the Blue Point ones I found in a secondhand / surplus shop in Vaasa, Finland!

 

[Pinemarten]

Cutting a box end is nowhere near as strong.

Nobody would consider a cut box wrench to be as strong as a proper flare wrench. But, after breaking a flare nut free with the open end....................a person could use the cut-open box end (field expedient) 12 pt to loosen and remove the fitting. Is it the elegant, best case scenario? Of course not! It might get somebody out of a jam though.

 

[Pinemarten]

I found these........

https://britishfasteners.com/whitworth-sized-crows-foot-set-of-9-pcs-1-8-ww-to-5-8-ww.html

 

[KnurledNut]

 

[Pinemarten]

If after trying a 3/16 Whitworth open end wrench unsuccessfully, I would fabricate a serviceable 3/16 Whitworth Crowfoot, I would get a Harbor Freight SAE Crowfoot set and take my diamond knife sharpener to the 7/16" wrench, With the flat face, I'd hone about 3 to 4 thousandths off each flat, checking as I went along.

If it worked out, I'd mark it so I didn't ******-up a 7/16 SAE fitting later on............LOL.

 

[snapmom]

Some Blue Point Whitworth Line wrenches. maybe missing a few, never seen a list.

 

[VolvoRyan]

There was a Swedish thread standard that used Whitworth threads with metric bolt heads. This actually makes a lot of sense, very typical of the practical Swedes, but confused me when I first found it.

Interesting. I recall BMW did a similar thing with the Buick/Rover V8's when they acquired Rover. American threads with metric heads. Yikes.

Volvo had a long history with English manufacturing. The first P1800's were built there, lots of bits and pieces over the years. The last generation of 6 cylinder engines was made in Ford's plant in Whales.

Thanks to all who have posted! This is all really fascinating!

-Ryan

 

[dscheidt]

Interesting. I recall BMW did a similar thing with the Buick/Rover V8's when they acquired Rover. American threads with metric heads. Yikes.

Detroit did the same thing in the 80s, during their transition to metric. New designs were metric, old stuff was sae. They had pressure from customers (probably Uncle Sam) to reduce the size of the toolkits needed to work on vehicles. Changing everything to metric wasn't practical, the solution was metric heads on sae bolts. (and abominations where you'd have parts that had a mix of metric and sae threads on the same part, because it was easy to make the electrical connectors metric, but the mounting to an engine had to stay sae.)