Brake Boosters explained

[wbute]

Flare nut spammers are what you are meant to use for fittings like brake lines.
You should be able to get imperial fittings.

[Dr Terry]

Flare nut spammers are what you are meant to use for fittings like brake lines.
You should be able to get imperial fittings.

What SLR_dave has said is 100% correct.

AFAIK pipe nuts with a 3/8" hex have not been available for over 15-20 years, but you can still buy them with metric threads. Confusing, isn't it ? Put simply, you can still purchase a full range of pipe nuts & fittings with imperial threads, but they have metric hex sizes.

In other words all pipe nuts with either 10mm or 3/8" threads are both manufactured from the same 10mm hex bar stock.

Rear axle brake pipes for WB (or early Commodore) are quite unique in that they have a 3/8" UNF nut at one end to suit the imperial wheel cylinders & a 10mm x 1 metric nut at the other to fit into the junction block integral with the rear axle to chassis brake hose.

You would need very good eyesight to be able to distinguish between a 3/8" hex & a 10mm hex without a spanner or vernier calipers. Even the most anal restorer (or concours judge) would not bother with such a minute difference. Also, a remade brake pipe utilising brand new pipe nuts looks a lot nicer than one made using old rusted or rounded nuts.

OK, you would need to 'infect' your old Holden imperial toolkit with the occasional metric spanner but I'm sure there are other areas on a WB that require metric tools. A set of good quality flare nut spanners (both SAE & metric) is a good investment & a must for any serious restorer.

Dr Terry