How to remove rust form cast iron - Cars & Trucks

wheel hubs are cast steel and are not rust treated. The rust may be from driving on snow/ice roads that have had salt on them. There is not much that can be done .You can trying a rust control agent ( phosphoric acid) which can be bought concentrated or in diluted form in rust prevention undercoats. You could then try using a good rust control paint that will withstand a lot of heat (remember that the brakes make everything hot)
If you can find an electro-plater in your area you may get the hubs cadmium plated or zink plated and this will arrest the rust.

Yes it is common,The hibs are made of cast iron.Any iron not sealed is going to rust. If your issue is cosmetic you can paint them. or spray them wiith some undercoating which is rubberized,works great. If you are concerned about the rust and the workmanship of your breaks over a period of time,not to worry,the rust doesn't do any harm to the strength of the metal.by the way,spray only the outside of the hubs.If you have rotors do not spray anything on them but break cleaner.I hope this helped.

Leaking head gaskets can and do cause this, the combustion gases are very corrosive and rusts the heck out of the cast iron.

Chances are the calipers are not at fault.You probably live in a northern state that puts salt on the roads in the winter time. Take a close look at the brake shoes. and where they mount. Often the manufacturer will put a thin metal plate over a caste iron iron caliper/brake pad mount. This is to give the brake pads a smooth surface to slide on. Take the the thin metal plates off of the bracket and file off the rust under neath the plates. The rust is expanding and pushing against the back of the thin plates causing the brake pads to bind and stick. This is then overheating the caliper and ruining it. Take a file and remove all the rust on the mounting brackets especially under the the brake pad slide plates. Once the brake pads move freely again the problem should go away.

That "mud" is actually rust. Back in the early eighties the EPA began mandating more and more MPG. Quickest and easiest way to begin doing that is to cut down on the vehicle weight. Engine block and cylinder head castings were made thinner and the use of nickel (which is heavier than steel or iron) in the alloy they are cast from was cut back. Nickel acts as a rust inhibitor and also helps as a "binding agent",
(without that nickel in there, blocks rust easily, reacting to the acid buildup as antifreeze deteriorates. Blocks and heads are also more prone to cracking as the nickel is very important, helping hold the iron together on a molecular level.
Flush the block really well, have the radiator flushed separately or it will plug up worse. I have seen some engines that were so badly rusted that the welch plugs needed to be removed to let the rust out. Or, replace it altogether.
Best thing you can do is change the antifreeze and do a simple water flush at least every two years.
If you don't you will be right back in the shop doing this same repair again!
OK, class dismissed!
Good luck!!

most brake system parts caliper,rotor/drums are cast iron and will have surface rust just driving in rain will soak ur wheels and brakes-water run off is normal and so is surface rust

No.

yes rust or iron oxide is formed when iron (Fe) reacts with the oxygen (O2) in the air and in water. the more oxygen the faster it will rust and since cold air is denser than hot air it could be said that metal will rust in the cold much faster. however once freezing point is reached the o2 in water cannot react with the iron and therefore is a nonreactant. only the o2 in the air would react so below freezing the process is slowed considerably. the liquid would affect the rate at which rust forms because of the water content in the liquid. if you submerge a screw in oil you could leave it indefinitely and it would not rust because there is no O2 whatsoever in it. whereas if you left it in apple juice the water in the mixture would eventually cause it to rust.

if your looking to keep somthing from rusting a coat of oil or wd40 then wrapped in plastic wrap is your best bet

This is a Yes, and No reply.

YES,
if the mechanic insures that the bore of the brake master cylinder, is free of rust pits, and if not, uses a brake hone to smooth out the bore. Closer inspection will reveal if the pits are too deep, and the master cylinder is unusable.

YES,
if the rubber components that go into the bore of the brake master cylinder, are installed in the correct direction, all the components are assembled in the correct order, and are pre-lubed with a little bit of clean brake fluid, before installing.

NO,
if any of the above criteria is not met.

The main thing is that the Brake Master Cylinder is in good repair. In good shape. If we are discussing the original brake master cylinder, for a 1981 Ford F100 pickup truck, we are discussing a master cylinder that is 28 years old, and has seen a lot of wear.

As a metallic object, such as a brake master cylinder heats up, (Engine heat, or even just the sun shining on the vehicle), then cools down, the moisture that is always present in the air, will form in the master cylinder.

Forms in droplets, at the bottom of the master cylinder's reservoir. This moisture creates rust, when it touches the cast iron brake master cylinder casting.
The rust clogs the ports at the bottom of the reservoir, and goes down into the bore of the master cylinder.

Makes rust pits in the bore, and harms other master cylinder components, then goes into the brake lines, and onto the rest of the brake system.

Me?
For the cost of a rebuilt or new brake master cylinder, compared to the expense of the master cylinder brake kit, and your labor time, I would go with a rebuilt, or new one.

Also this is part of the Brake System, and there's no fooling around with brakes! Your life and/or someone else, Depends on those brakes!