Mazda MX5/Miata MK4 - same Rust Issues as the NA, NB, NC??

Time to check out the underside of our 2017 ND and plan its treatment.

[@midlifemotors5050]

Been putting off the inevitable!!

[@Steve-uf8pk]

I recommend using LPS3, which prevents rust & corrosion designed mainly for use on aircraft, which operate in much more demanding environment than the average car. It is safe to use if overspray gets on rubber, plastics, fabric, paints and metals. It inhibits exfoliation and filiform corrosion of aluminium and corrosion on steel, works as a self-healing, clear, soft, waxy film, which can be reapplied every couple of years with a simple pressure pump. I bought a waxoyl applicator which worked great and comes with an attachment for treating importantly the inside of the chassis members, which can be cleaned out after use for years to come. Used it on my new ND2, took a good day to cover all the steel chassis/frame members but very satisfying and easy to apply……

[@midlifemotors5050]

Great info, many thanks 👍 The comments have really helped, was fairly down over weekend tbh. Having a think right now on best way forward. Thinking of getting the professionals in. Should make for some good content at least 😎

[@bastog2670]

my 2017 mx5 nd has rust on about the same spots as you have, chassis is fine but subframe and bolts mostly have spots

[@williambeckey4506]

My god. I invite you to look under an older NA or and NB. I’d eat my dinner off this ND1 here.

[@SamSayaz]

Exactly what I'm thinking. ND looks fine all over

[@gzk6nk]

I had a Mk2 from new, but only for 3 years before trading it up to a new Mk3. Had that for 14 years and like all my cars it lives outside and is my daily driver so saw salty roads. It did get an MOT advisory at 13 years for sill rust but not structurally significant. Had that sorted and the guy said "that MOT inspector was protecting his backside, Your car is fine". Next MOT - no advisories. So at 14 trouble free years I traded the Mk 3 for a new ND2 in 2021. It is by far the best MX5 yet. I expect it to last just as the Mk3 did. Surface rust underneath that looks horrid, but nowt serious. If I'm still around when it's 14 years old (I'm in my mid '70s so will be mid '80s by then) and if I still have it by then, that'll do me. Heck! This car will likely out-live me! Vince

[@midlifemotors5050]

Fair enough. Maybe I’m being a bit too paranoid, my OCD kicking in 🤣 Hope I’m still doing what you’re doing in 20 years time. Fair play fella 👍

[@mmmmmmmmmmmmmmm420]

I wish you well. I'm in my fifties and a life-long car enthusiast. I've never wanted to own a Mazda, despite their engineering prowess because of their consistent unwillingness to protect their cars from corrosion.

[@midlifemotors5050]

Same age here and after many cars the MX5 is the one that does it for me. They’re mega and IMO the MK4 is the best of the bunch. It’ll get protected, going to get the professionals to quote, and we’ll move on. Just a blip 🤞

[@Ifitwerks]

The rear brake calliper body is cast aluminium.

[@bimmer4624]

A quick rub over with wire brush and spray over with Lanoline a natural oil and safe. Do this once a year before winter sets in.

[@pauldarlington9157]

I’ve got a 2016 ND which has been garaged and washed underneath on the odd occasions it’s been out in the winter. We don’t live near the coast and I’ve just had it steam cleaned and treated with Lanogaurd and there was no sign of any rust

[@midlifemotors5050]

Fair enough, wise to get it protected though 👍

[@garycongdon5540]

I'm another Bilt Hamber vote if doing it yourself. After good preparation BH UC or UB for the visible bits and get into all the hollow areas with BH S50 cavity treatment.

[@midlifemotors5050]

Many thanks 👍

[@CarBore]

Oh my god DONT triggering me already just reading the title alone gives me shivers after the last year!

[@midlifemotors5050]

🤣🤣 hence the tribute fella. Did you spot the pepsi max 😉

[@CarBore]

@@midlifemotors5050 😂😂I did wonder at that is he openly trolling me here??? 🤣 I’ve bought 2 tins of that ACF 50 stuff or whatever it’s called that bikers use to spray on later this year (mot permitting) once you’ve got it tidied up that stuff appears to acts as an excellent barrier.

[@midlifemotors5050]

@@CarBore I'm wondering about maybe going to Preserve & Protect over in Johnstone for the full treatment. Then it's done and can forget about it. Having a little think just now 🤔

[@CarBore]

@@midlifemotors5050 thats a good shout actually heard some excellent stuff about them to be honest when it comes to protecting 5's if you fancy a drive Arnand Viad gets amazing write ups on the 5 forums but he's down in that little fishing village of London.

[@midlifemotors5050]

@@CarBore Booked in with P & P 👍

[@kenpallister5804]

Bilt Hamber. It's amazing stuff. Lots of light coats. Don't go in too heavy.

[@midlifemotors5050]

Lots of suggestions for Bilt Hamber, thanks 👍

[@MrGrentch]

@emotors5050I'd be on the Bilt bus too. In 05 I imported a Honda from Japan to Ireland and still drive it today in all weathers. Being paranoid about tin worm, the week it showed up I fired waxoyl into it, but I always found it a pain to apply tbh. I soon discovered the BH stuff and have been using it ever since. Check it and top up once a year. Sills, inner wheel arches, inside doors, hatch, leading edge of bonnet, along seams, suspension bits and bobs etc. Then after a few days and it solidifies up I go around making sure all drain holes are clear. Now 90's Honda's have a habit of making 80's Lancias look solid😁, but so far so good. I'd actually go so far as to say it's got a good bit less rust than your Mazda. That said and from what I can see what rust you have looks surface and easily treatable. The bugger with rust is it's too often the parts you _can't_ see. PS subbed for more. 🙂👍

[@lm971120]

I don't yet own an MX-5 but these brakes don't look good to me, could be simple as just the disc and pads need changing, and the fact it's not used much (and based in Scotland like myself), but based on my experiences a irregular wear pattern is usually a bit more than just that (ie. new disc and pads will soon become like that in less than a year). Since you are painting the callipers, perhaps worth checking if the brake slider pins are moving freely, see if rubber boots are damaged, and if the callipers seem alright? I assume at the moment these discs either run hot after a short drive, or produce a horrible squeal, or both, so need to be attended soon. At this stage they definitely won't sort themselves out.

[@midlifemotors5050]

Will check but tbh they do that quite often if the car is left, even for a short period. Quick 20 minute blast and they’re fine again. The rear brakes on the 5s do very little of the work. Guess that’s why they’re so tiny.

[@RichardOzanne]

Cards on the table - I get paranoid about rust. What I've done in the past, which I'm sure some will agree with, some not, is to clean back to bare metal then treat with something like Galvafroid cold-galvanising paint, then put a top coat over that (satin black etc). Once that's cured for a week or so it should be pretty well sorted, but if you want to, then I guess there's no reason not to put some kind of rust inhibitor over the top. We're at the opposite end of the UK to you but also have a similar proximity to the sea and the same salty air. I'd get those springs powder coated if I were you (assuming they have not got bad pitting in the surface)

[@midlifemotors5050]

I'm with you which is why i'm umming and ahhing about maybe getting a professional company involved. Going to have a think about things over the next week. See what feedback we get and take it from there. The springs are bad (not impressed) however coilovers are on the way so not too worried about the state of those & the shocks. Thanks for the input 👍

[@sokgso]

Hmm, not great. You would think it would hold up better, even in the salty ocean air. Do the importer/Mazda UK treat the cars once they arrive in the UK?

[@midlifemotors5050]

Not particularly well by the looks of it & getting away with it for 30+ years now!!

[@demon1954]

No

[@midlifemotors5050]

@@demon1954 Yes…unfortunately 😳

[@Archiegser]

You need to get behind the wheel arch liners they are rust traps and then decide if it's rusty or not. Most of what you are seeing is surface rust light corrosion. The parts are only e-coated oem. Some wax is sprayed in the more hidden areas but they are not rust proofed by any means, Proofing = weight.. Good luck and enjoy.

[@midlifemotors5050]

Good point 👍 The professionals are getting involved now so fingers crossed things will get better soon 🤞

[@Archiegser]

@@midlifemotors5050 Only if you do it yourself or some pro to do it for ££££'s.

[@stevenhill6214]

Given the salty environment, i'm surprised it's not worse than that. A fine wire brush in a drill should sort it out though (PPE required obviously) followed by whatever rust protection you prefer. Really surprised at the condition of those coil springs though....i would be fairly pi**ed off by that!

[@midlifemotors5050]

It's not too far gone, which is good. But deffo needs attention now. The springs are bad...excuse for coilovers though 😀

[@fasthracing]

Umm. Bilstien dampers (even the aftermarket none "OEM" ones) are known for rusting. I had some Eibach springs on a car (Badged as Mountune) and after 6000 miles and 2 years on the car they came up as an MOT advisory! I am though a bit surprised at the amount of surface rust on it. Its almost as if they just Halfords rattle can finish stuff. My 2013 Ford Fiesta ST is just as bad. Cost cutting comes to mind.

[@midlifemotors5050]

It is terrible really considering the car has only done 10k miles and neither us or the previous owner used it in winter!! Going coilovers so the suspension will get changed, every cloud and all that 😀 As for the rust itself, having slept on it think it’s going to go to the professionals. All the comments have really helped. Was fairly down over the weekend. Onwards, watch this space…

[@fasthracing]

I await developments.@@midlifemotors5050

[@Cheekyweekesy]

Use Bilt Hamber Dynax UC to seal and Atom Mac regularly when you wash the car

[@midlifemotors5050]

Many thanks 👍

[@thuriumscreamer5761]

Same on 124 spider here in Italy. No rust on body but subframe and all suspension bolts are rusty. 595 abarth and 500x used in mountain with salt etc no signs of rust after so many years. It's something about japanese cars, no good rust protections

[@midlifemotors5050]

It is poor form tbh. We have Toyotas too that live in the same environment, no issues.

[@richfixescars]

Pretty normal on a 6 year old MX-5. Bilt Hamber Dynax clear is what you need. Mask it off, wear a mask, and spray it on. Front subframe will be similar.

[@midlifemotors5050]

Think you’re right, it will be. How hard can it be for Mazda to just do it properly in this day and age??!!

[@e1337prodigy]

When I test drove a mx5 nD, the salesman said we dont sell the NC anymore because of the rust issues, the new ones don't suffer with these.

[@midlifemotors5050]

Guess that proves the theory…never trust a car salesman 🤣

[@aleddavies770]

Doesn’t look very clean underneath considering the mileage

[@mgv.videostudio]

I went for a test drive today. The authorized dealer told me that the latest models have galvanized sheet metal and a 12 year warranty against rust. I am from Europe, Slovenia.

[@midlifemotors5050]

Yeah, think they told me exactly the same 🤣🤣 No big deal though, just get it protected early on and all will be fine 👍

[@ravyn65]

In Poland one of the journalists went balistic with mazda over this statement. He ordered test in one of the local Universities. They have proven that Mazdas are not galvanized. It is only zinc layer within primary coating. But structure of coating is not continous and crystals are lot bigger than those created during galvanization process. (It is worse in terms of anticorosion properties in comparison to galvanization process)

[@KunziDoesStuff]

I got mine rust protected by Anand Vaid last March. You may have come across his name before in one of the forums or Facebook groups. He does a really thorough job and I was very pleased with the result. The only trouble for you is that he is based in London and will need to keep the car for a week.

[@midlifemotors5050]

Yeah, seen his work, top notch. We have a similar specialist based just outside Glasgow. Managed to get booked in on the 22nd March. Was a Mk4 coming out and another going in this morning when I went to get a quote. Feeling a bit better about things now 👍

[@KunziDoesStuff]

Might be worth checking the rear hub bushings too since you have the car up on jacks. Had to get mine replaced last September otherwise would have failed its MOT!@@midlifemotors5050

[@KunziDoesStuff]

Roddisons in Sheffield sorted me out with that, but I think you can get a kit and DIY it or if you know a specialist in your area.

[@1ABY]

Imagine how it would look if you had been using over winter months without any protection dread to think

[@midlifemotors5050]

Exactly. And there’s me thinking they would add some protection from factory 🤣😀 Time to start phoning around today 👍

[@BlackLines]

Yes I think it'll be worthwhile just sanding it off and sealing it while it's still minor - you'll wish you had in five years time if you don't :) One thing you might want to check (although I don't know enough about Mazdas to know if they're affected by it) is to remove the plastic facing covers off the sills (the side strips) and check underneath. On my Celica there's a channel running down from the top rear of the bonnet into the wheel arch and all sorts of stuff gets stuck in two places: One, just behind the front wheel arch at the bottom. Two, at the rear of the sill just before the rear arches ... in both cases on mine, the sills were perfect except in those two places where the muck was stored and it had started to rot through simply because of the damp and grime being stuck against the sills. I've just taken my covers off again a year after having had it patched and lo and behold there were some leaves and detritus accumulating again so definitely worth doing.

[@midlifemotors5050]

Thanks for the info fella, much appreciated 👍 Felling a bit deflated this evening, going to sleep on it and decide how to move forward tomorrow. Thinking of getting some quotes. Seems a professional job may be the best long term solution 🤔

[@collinwaugh939]

mx5s are just terrible for rust a few years ago i had a nc on a 2008 plate thought it was in great shape till it was up on a ramp it was just rusting away underneath mechanic said it would not make it threw the next mot without welding and a lot of rusted out parts replacement ! not good !!

[@midlifemotors5050]

You’re right it’s really not good. We’ve a 2006 MR2 also which is pristine by comparison. How have Mazda done so badly for so long?? Surely in this day and age it’s not that hard!!

[@collinwaugh939]

the weird thing is i traded my mx5 in for a blue mr2 roadster 2004 and it had zero rust on it too ! i kept it for 3 years and i wish i never sold it !! 🙁@@midlifemotors5050

[@justgetoutanddrive]

Get it treated ASAP

[@midlifemotors5050]

Yup, that's the plan. Just wondering now whether or not to get the professionals involved 🤔

[@the1beard]

OMG that is terrible I had a Yamaha motorcycle and a friend bought a Honda at the same time his honda started rusting year 2 my Yamaha still rust free after 6 years his Honda was terrible .. the difference was Yamaha had better quality steel and he washed his Honda ever few weeks with all the degreaser products I washed the Yamaha with just Autoglym car shampoo and used wd40 on the exposed bits

[@midlifemotors5050]

Not good but MX5s are known for it. Fortunately caught early enough so away being treated and protected now, phew!!

[@stephenlaw9827]

Use lanogard.

[@patterdalezipsuzilil]

F.... hate rust under cars i used to hate mot time here you go mate have you seen this when on ramps 😂😂😂😂 there is good sprays it turns rust black and stops

[@midlifemotors5050]

So true, grrrrrrrrr!! Bit deflated tbh, just taking 5 before deciding how to move forward 🤔

[@jasondixon9095]

Spray the undercoating spray

[@kellypaws]

A Mazda 150 metres from the sea? Don't do that. It won't go well. And it's not meant to be slagging it off. I've just had a Mazda and frankly, it was keen to rust. Even well, well away from the sea.

[@midlifemotors5050]

🤣🤣 It didn’t go well. Sorted now though, phew!! Why can’t Mazda just build it properly by now 🤔

[@kellypaws]

@@midlifemotors5050 I’m glad you’re sorted. No amount of rust protection for a Mazda is too much. They sadly have no grasp of the concept of rust protection.

[@vgama]

Why don't mazda fix this problem already? It's going on for 30 years...

[@midlifemotors5050]

Someone high up in the motoring press really needs to ask exactly that tbh It’s 2024 and Mazda can’t even rustproof a car!!

[@varmastiko2908]

They don't fix it because they don't need to. People will keep buying and the media will keep lying.