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MG TD TF 1500 - Moss Motors brake lines

I just bought a set of brake lines from Moss Motors. From the way they are packaged I can't tell whether they are actually the correct ones for a TD. The instructions are generic and they need to be bent into the correct shapes. Has anyone ever used these before? I am trying to decide whether to send them back.
W Stephens

Hi W, brake lines are always supplied coiled. You need to use the old lines as a template for bending. You can check the length of the lines from the original parts list (TD or TF - they are the same). Good luck. Matt
Matt Davis

Are they copper or steel ?

SPW
STEVE WINCZE

The Moss lines I got a couple years ago were absolutely beautiful, with nice brass end fittings. You can use a tubing bender, or a round can, etc. to bend. Easy to do. Have never heard of pre-bent lines for a T-series so far. George
George Butz

As I've been told, their nickle/copper. They straighten out beautifully and bend with ease using a proper bender. I matched mine to the originals. Very nice. PJ


P Jennings

I also endorse the MM brake lines-----have used them on MGA, MGTD, and TR3. Have had no problems.
TCK Tom

Thanks everyone. Bending brake lines makes me nervous but I'll give it a shot. I don't have the old ones to match so it will be a little complicated. Any recommendations on a bending tool or are they all pretty much the same?
W Stephens

Without the old lines, you will probably have to have another TD on hand to get this right. They have a lot of unusual bends. The Moss lines are great Ni-Cu parts and large radii can be bent without a tool. The tool is needed for short radii. Mike
MW Davis

Most all of the radius bends are not sharp, so you can bend around a spray can or something. Just don't kink. Definitely a problem w/o a pattern- another car would be great, or search Dave B's website for chassis pictures.
George Butz

...mine came coiled and had to be bent...I bought one of those little plier type benders and threw it away after about two bends....using your hands works just fine....and use the old ones as a guide...or photos to show the major bends...

good luck....

(mine were also lovely copper with brass fittings)
gblawson(gordon- TD27667)

RE: copper

I'm not sure copper lines is such a good idea. I found this on the Moss Motors website:
http://www.mossmotors.com/SiteGraphics/Pages/Brake_Fluid/brake_fluid_long.html


==============================================
Understanding the Corrosion Process

Water contamination has recently been shown to be a contributing factor, not the sole cause of corrosion. To understand corrosion, we need to know a little bit more about the process. The fundamental principle driving corrosion of iron or steel is simple: The natural progression is from less stable to more stable, and rust produced by the combination of oxygen and iron or steel is more stable than pure iron or steel. Copper also reacts with oxygen for the same basic reason. Most metals exposed to oxygen form “a thin layer of the metal on the surface which reacts with oxygen in the air to form a dense oxide film. This film "passivates" and protects the rest of the metal by acting as a barrier to greatly reduce further reaction with oxygen.” [40] This film will be partially dissolved by water or other solvents, reducing the protection it provides. High heat and acids will accelerate the process. Not much can be done to limit the amount of oxygen dissolved in the brake fluid, and the brakes inherently generate heat. The acids can be neutralized to a certain extent by adding alkaline chemicals to the brake fluid, which is why brake fluid has a pH of 7 to 11.5. Brake fluid manufacturers also add chemicals to the fluid that stick to and coat the metal surface, providing a barrier in addition to the metal oxide film. [40] Corrosion is a complex process, and different metals behave differently. Metals that are used in combination also behave differently. Some metals are inherently more corrosion resistant than others. Consider zinc, iron, and copper. Of the three, copper is the least prone to corrosion, and zinc is the most prone to corrosion. Iron is in the middle. [...] If you put copper and iron together, the iron will corrode before the copper will. The relevance to brake systems is this: where copper metal has already been corroded and dissolved into a liquid, it will attack any iron metal (steel) it comes in contact with. This is because, like zinc does for iron, the iron will sacrifice itself for the copper. The result is that dissolved copper will come out of solution and plate onto the surrounding steel, while a proportional amount of iron will dissolve and go into solution. While the initial corrosion reaction of copper requires oxygen and acid, the second reaction where dissolved copper corrodes the iron does not have this requirement. This chemistry is important in explaining what can happen in brake systems with aged and degraded brake fluid. [40] The corrosion inhibitors that would normally protect the iron and steel to a certain extent break down over time with heat and the corrosive effects of the copper will increase. All it takes is time: another extensive study found that the buffer capacity and inhibitor concentrations "drop to less than 10% of their initial levels after only 30 months of service." [27] The NIST (National Institute of Standards and Technology) study does show that internal corrosion does take place as a result of depletion of the corrosion inhibitors in the brake fluid and the accumulation of water in the brake fluid over time.[40]
Rob Edwards

I tried bending by hand with some success but finally got a cheap bender at Napa. Buy some cheap brake line there and practice first! My humble opinion....
Ed
efh Haskell

Rob, Other European auto manufactures have been using the copper/nickel brake lines for some time now and have reported no ill effects. I believe Volvo, for one, uses it. It will also withstand high pressures. What we see in restoring these cars is 50 to 60 years or more of the effects of corrosion and some, even using steel lines, are in remarkably good condition. I for one am certainly not going to worry about my TF rusting away! Maybe my great grand children might have a problem with it, if it's still in the family at that time. (Grin). PJ
P Jennings

I dimmly remember when Moss came out with these lines a few years ago. They had some technical details, and told the major car makers that use the same material. Yes, pure copper will corrode. The main problem I have had wih the originals is the flare distorting and then cracking. George
George Butz

copper/nickel is completely different from pure copper. the most significant problem with copper lines is not the corrosion..they will crack long before they corrode. i bent my moss motors lines by hand and had no problems. copper/nickel lines are a great product. corrosion resistant and as the guys here described, easily shaped. regards, tom
tom peterson

When I did the TD a few years ago I got all new lines from Abingdon. Quality product and correct for an authentic restoration. When I did the TF last year I got the lines from Moss. I was quite impressed with the quality, although they are an upgrade from the original lines. The nickel copper Moss lines were much easier to bend, and look great.
-David
D. Sander

A number of years ago, I got very alarmed when the use of "copper" brake lines was a subject for discussion on this BBS. My imagination took me to the copper tubing available at the local hardware store. At the time I was considering replacing the original brake lines on my TD, and looking to see what was available. I went to a specialty brake shop in Calgary and discussed the use of copper with a very knowlegable guy. He explained the copper/nickel lines to me and I was much relieved. My concern would be for newer members who might think they can just go to the local hardware store and get the copper tubing for their brake lines. I found the bending to shape of the new lines not to be a problem. The material is easily formed with or without a tube bender. The tube bender gives a much neater bend, and less likely to crimp the line. I supplied the brake shop with the required lenghts, and they supplied the end fittings and flared the ends.I was very pleased with the results.

George
George Raham [TD4224]

>the most significant problem with copper lines is not the corrosion..they will crack long before they corrode.

My takeaway from the passage I quoted was not that the copper in the lines will react & corrode -- in fact, just the opposite. They seem to be saying the copper will /not/ corrode but instead the iron wheel and master cylinders will corrode more quickly due to the copper in the system. Think of the sacrificial anode on a boat propeller shaft, except in this case the anode is your wheel cylinder!

Those of you using this tubing -- what's the condition of the cast iron components?
Rob Edwards

Rob,
I am unsure of what you are suggesting. Does the copper component in the brake lines, attack the cast iron in the braking system? Could you specify which parts might be subject to some type of deterioration.
Not being a metallurgist, I am keen to understand. The only part I can think of would be the master cylinder.

George
George Raham [TD4224]

To prevent corrosion, use DOT 5 (silicone) fluid.
-David
D. Sander

>Does the copper component in the brake lines, attack the cast iron in the braking system?

According to the paragraph I quoted that I found on the Moss website, yes, in a sense it does. Here's a more precise description from Wikipedia:
===========================================
Galvanic anode
From Wikipedia, the free encyclopedia

A galvanic anode is the main component of a galvanic cathodic protection (CP) system used to protect buried or submerged metal structures from corrosion.

They are made from a metal alloy with a more "active" voltage (more negative electrochemical potential) than the metal of the structure. The difference in potential between the two metals means that the galvanic anode corrodes, so that the anode material is consumed in preference to the structure.

============================================

The Moss article is suggesting that iron has a more active voltage potential (using the terms from the Wikipedia article) than does copper, so as corrosion occurs, the iron in the the system is consumed in preference to the copper. In our cars, the wheel cylinders and the master cylinder are made of cast iron.

Obviously pure copper lines would be a bad idea for a host of reasons. Whether there's enough copper in the cupro-nickel material and whether it can be liberated to cause problems, I don't know. Could just be me being paranoid. ;-)
Rob Edwards

Rob, the wheel cylinders are some type of pot metal or aluminum but definitely not cast iron. My master is brass sleeved, thousands of those out there and I have never heard of a corrosion problem between the dissimilar brass and iron. The I think there is zero chance of a problem with corrosion using silicone fluid in a set up like this. Have seen several stock cast iron masters completely rust up, and wheel cylinders badly corrode using regular old brake fluid and the original steel lines! George
George Butz

The I think there is zero chance of a problem with corrosion using silicone fluid in a set up like this.

I agree George, I have silicone in both the MGB and the TF. Of course both systems were complete with new lines and rebuilt master cyls and wheel cyls. PJ
P Jennings

>the wheel cylinders are some type of pot metal or aluminum but definitely not cast iron.

Duh! Of course, you're correct. I had the wrong car in mind. The master (if it hasn't been resleeved as yours has) is definitey CI though.

I agree with the DOT 5 fluid -- I run it in my cars!
Rob Edwards

This thread was discussed between 24/12/2011 and 25/12/2011

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