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[Spider]

There are a variety of fittings needed, depending on what you're plumbing up
 

 

From left to right: These are Brass and Rubbish, stay away from these (Local suppliers seem to only be able to offer them), Next, these are the original Oz Style ones as found in the rear subframe, Next are the same as previous, but new from the UK, Next is the M10 type for the Tandem M/Cs and Last is the 3/8 UNF ones that cover most of the car.

 

Before we go too far on fittings, considering tubing used for Brake Lines and Making off of the flared ends, there's some slang terms floating about and these can make for some confusion when taking about them. The BMC / Leyland / Rover factories in the UK and Australia had a standard for these, CT-1 and CT-4. These were to SAE Standards J512 and J513. When referring to the type of flares used in a particular Brake Line application, these are the terms I prefer to use as there's some over-lap and gaps in the various slang terms I've heard over the years.

 

SAE J512 here;- 

 

https://www.sae.org/...Tr9CB2LTUf98M9Z

 

NOTE the terms used there is Double Flare and Inverted Flare

It is possible that BMC / Leyland plants in other countries used different standards for the brake line fittings of the vehicles they assembled. All I can suggest here is to use some care in checking however these days 99% or more of the replacement parts come from the UK, so the SAE Standards would apply to them.

 

All countries have standards to which various Automotive Components need to be manufactured or tested or assembled to. Brakes of course have a standard. In all countries throughout the world, where it comes to brake lines and the type of flares they have, while the standard for the shape and size may vary between them, ie SAE, JIN, DIN etc, they all agree that the flares must be a minimum of (to use the SAE term) double flared, here's an extract from the Australian Standard LG for them;-

 

 

SAE J1047 supersedes J513, however the terminology is the same, this has just been broadened to include metric and a few other standards.

Note the term used here is double flared.

 

There's two basic types of flares used on Minis and Mokes.

 

First and most common on the vehicles is a Double Flare (BMC Standard CT-1).

 

 

Double Flare to SAE J512 and it's cross sectional appearance.

 

 

The other type of flare is the Inverted Flare (BMC Standard CT-4)

 

 

 

Inverted Flare to SAE J512 and it's cross sectional appearance.

 

The Inverted Flare is accepted under various vehicle standards as the flare is formed by having 2 folds formed in the tubing.

 

This is the double flare, usually used with the M10 and the 3/8" UNF Tube nut (last two on the right above)

Generally fitted in to something like this;-

 

 

 

 

This is an Invert Flare, as used with the hoses on the rear trailing arm, the Female Tube Nuts (first 3 from left above) are used with these;-
 

 

Fitted on to these

 

 

[Spider]

What fitting sizes do you need ?

 

Early on the all the fittings were easy, being 3/8" UNF, but as the years went by Metric has crept in to some of the fittings, mostly M10 x 1.0.

If you are unsure if a Port is 3/8" UNF or M10 x 1.0, as they are very close and a 3/8" UNF Tube Nut will screw in to an M10 x 1.0 Port, but is potentially dangerous, one way to work out what you have is if you have an old tube nut that you know came from it, try screwing it in to a wheel nut. If it goes in, it's most likely 3/8" UNF and if it doesn't, then M10 x 1.0. Another similar way is to obtain an M10 x 1.0 screw and use that for testing.

 

If you are using Non-genuine parts, you must check what Thread they are as well as the type of Flare needed, including those to DIN standards;-

 

This is a list of Factory Brake Parts and the various threads used.

 

 

Master Cylinders

 

The Single Circuit Master Cylinders are 3/8" UNF (including Clutch).

 

The CMC 159 and GMC160 Tandem Masters are 3/8" UNF on both ports.

The GMC 167 (sometimes called a Green Tag) Master Cylinder is M10 x 1.0 on both ports. There is an earlier version of these (black tag) that were 3/8" UNF.

The GMC 227 (yellow tag) is M10 x 1.0 and M12.x 1.0. 

 

The GMC 242 and GMC90376 are M10 x 1.0. 

 

 

Valves

The FAM7821 and the FAM4670 are M10 x 1.0

All other Brake Valves are 3/8" UNF

 

 

Brass Unions

All Brass Tee's and other Unions are 3/8" UNF.

 

 

Hoses

All Brake Hoses are 3/8" UNF

 

 

Wheel Cylinders

All Wheel Cylinders are 3/8" UNF.

 

 

Brake Calipers - 2 Pot type

 

Factory twin pot Brake Calipers, as fitted to the Cooper, Cooper S, 1275 GT and all late Minis are 3/8" UNF, though these have the hoses screwed directly in to them, with a copper sealing washer.

 

 

Line Joiners

 

Caution: These can be a minefield, you need to check what you have.

 

These were used on some models to usually to join long lengths of tubing sections or in some awkward places.
 

These did change a few times over the years, with a mix of 3/8" UNF and M10 x 1.0 as well as taking Double Flare and Invert Flare (refer Post #1 above to the correct description of these).

 

You will need to confirm the Thread and Flare type needed here.