Rusting on 70 plate MG ZS EV wheel metal inners

[TinaH]

Hi, has anyone else noticed rusting on the visible metal parts of the wheels on their MG ZS EV? Sorry for the vague description, I have no idea what this part of the wheel is called! I know we’ve had a lot of rain at times in the UK since March 2020, but I would not have expected rust already? If ever!

 

[Marc Nagtegaal]

Do you mean the breaking plates?

 

[TinaH]

Do you mean the breaking plates?

 

[TinaH]

not sure these photos are clear enough to show, but the flat disc and the matt silver section are rusty on three wheel, drivers side front is still rust-free. Is it something I should be concerned about??

 

[Kithmo]

All cars are like this.

 

[Alb]

As above, most cars are the same.
These parts are better off not having a cosmetic paint coat in the first place.

 

[ARealHuman]

I have that on mine, not overly worried about it. If I was a teenager again, I'd probably take the wheels off and treat/paint the rusty areas. In my middle age, I just can't be arsed! And as others have said, most cars, not just MGs, seems to have this problem.

 

[Alb]

Here's a brake rotor from my Focus.
It's an unpainted cast component so surface oxidisation is normal.

 

[Severnless]

Really sorry to say this but, it Might help if you cleaned the car more regularly, so getting ride of any residual salt from the road grime.

 

[Lovemyev]

And as others have said, most cars, not just MGs, seems to have this problem.

I agree.
Most of the VAG models look terrible after a short while, the hub ( not the disc itself ) will go rusty and it looks unsightly through the rear alloys.
You could always rectify this problem by removing the wheel and treating the outer drum of the disc with a silver heat resistant paint.
But the small problem is, when they install the alloys wheels, onto the mild steel hubs, after a short while corrosion take place because of the dissimilar materials.
Making it very difficult to remove the road wheel due to the build up of white furry corrosion.
Of course, this could be totally avoided by the use of a slight smear of grease around the hub before the wheels are installed.
But that’s WAY to easy !.
Every car I have owned with alloy wheels, I have removed them almost straight away and cleaned the surface rust from the hubs, then applied a thin film of copper grease, around the steel boss, before refitting the road wheels.
I learnt this lesson many years ago when travelling to work at 5.00 am one morning and got a puncture in the O/S/R tyre.
The car was a VW Golf and was less than 9 months old,after jacking up the car and removing the bolts, do you think I could get that alloy wheel off the car !.
Managed to get a lift into work and then returned at diner time with a 2lb copper and hide hammer !.
After turning and beating the tyre from back, after about 3 minutes, the wheel finally released from the hub.
White corrosion had fixed the rim solid to the hub in that very short time.
Mind you, the car could have been built ages before I bought it of course.
Picture this, you are unlucky enough to get a puncture, hey …. but not to worry because you have invested in either a space saver or a full sized rim for your ZS EV !.
Here is the frustrating part, you can’t get the alloy off the car in order to fit the bloody spare !.
“Top Tip”.
Eliminate this by doing what I have done folks, you will thank me when it happens.
The longer that alloy is on the car, the less chance you have of getting it off at the side of the road, trust me I know !.
Remember, the dealer is very unlikely to remove the road wheels UNLESS you have a problem that necessitates there removal.
Brake pad wear is inspected without the wheels being removed.
In theory, if you are puncture free, then the first people to remove any wheels, is likely to be a tyre shop when they replace your front tyres.
Our yourself if you get a puncture that is.
Of course, you could leave it to the AA.
But if you have purchased a spare, you are likely to tattle the job yourself and be back on the move as quickly as possible.
Depending on your driving style and usage, it could be over two years+ before the wheels are removed for the very first time,
from the wheels being first installed at the factory.
Good luck with that one !.
I have removed road wheels from cars I have owed and pre treated with copper grease after 3 years and the wheel just falls off the car.
They are SO free from corrosion, it is a good idea to leave one bolt slightly holding on the road wheel onto the hub, until you are ready to finally release the wheel from the hub.

 

[ARealHuman]

OK, so I'm confused. I thought the rust problem wasn't the edge of the discs as in the larger photo above (assuming that's what it's showing, and this can get you an MOT advisory in my experience which is odd IMHO), but the area of the hub above the wheel nut in the 12 o'clock position in the @TinaH's post.

Good advice @Lovemyev, thanks

 

[Cocijo]

Yes - it’s not entirely clear from the OP. My experience is that all brake hubs oxidize as do brake calipers. The outer (the edge) circumference of the brake disc has no pad contact and so that always gets rusty too. You can paint the hubs (i did this on a couple of BMW’s that I owned), and if you want to also the brake calipers. As long as the braking pad contact surface of the disc is free from rust you’re ok. As you say MOT centres have rules on brake disc corrosion and thickness as do the manufacturers.
the silver paint has stayed on my hubs so far.

 

[Electrifried]

Nothing unusual there, you will see that on any brake disc. Let’s face it you are looking at bare metal disc it is bound to rust over time unless you want to spend multiple thousands of pounds on ceramic brakes.

 

[Brianlescargot]

Every car‘s brake disc rusts when it isn’t used for a period of time. Give it some hard braking and it will disappear.

 

[Alb]

I can see this being a problem for the rears in particular over time because they get little use with KERS and when they do come into play, they are relatively lightly loaded.

 

[Exdro]

Hi, has anyone else noticed rusting on the visible metal parts of the wheels on their MG ZS EV? Sorry for the vague description, I have no idea what this part of the wheel is called! I know we’ve had a lot of rain at times in the UK since March 2020, but I would not have expected rust already? If ever!

This is perfectly normal on all cars with metal disc brakes. Heavy braking will remove it. The reason that you may be more aware of it on your MG EV is that the KERS system does not apply the brakes and slows the vehicle by electrical regeneration. Therefore the surface corrosion is not polished off as you rarely have to resort to heavy braking depending on your driving style. Nothing to worry about.

 

[Cocijo]

I thought this might help those who are struggling a little with the different names of parts.

 

[Brianlescargot]

I can see this being a problem for the rears in particular over time because they get little use with KERS and when they do come into play, they are relatively lightly loaded.

The MG regenerative braking system is not all that strong compared to other EVs. We have a BMW i3 and it is easily twice Sam strong as the MG and genuinely capable of one pedal driving yet the discs on ours are still fine. As I stated previously just give it a good hard brake every now and then, it will soon take that surface rust away.

 

[Alb]

I'm not entirely convinced what I'm seeing on my own discs is surface rust but I agree that occasional hard braking is beneficial with respect to maintaining a good surface.

 

[Phil752]

Do you mean the discs or the calipers