These are fair comments.
I think most people see cars as a top-side affair only and barely give a second thought to the underneath. Probably a result of the explosion of PCP and other ways to access a car only for the first three years of its life. I am one of those but then got an MX-5 as an ‘enthusiast’ and am learning that the on-going ownership proposition requires more input. That’s ok, I was ready for it and owned older cars when I was younger. But I think for some the under treatment is an unwelcome addition to the whole proposition. It’s six of one, half a dozen of the other though - the Mazda guy today said that Z4s have plenty of problems and Mazdas are much more reliable. They just have this weakness arising from the lack of undersealing, itself a function of non-salted Japanese roads.
I did ask my Waxoyl guy about ‘topping up’ but he said basically come back in 3-5 years and do the whole lot all over again as a preventative. There was a technical reason for that, but I can’t quite remember what he said. I am sure there are different schools of thought on this. For me, I’ve done it now and don’t really want to think about it again but I will probably veer away from driving in the wet generally and especially over the winter period so that my blissful ignorance doesn’t come back to haunt me any time soon.
It will dry out and split, that is why the " every 2 years" to check ,although there are far better products out there now than old school waxoyl now to use, and some parts of Japan do use salt buddy.
M-m
Who knew re. salt in Japan! I guess it does snow in parts there…
I never said anything about slap dash merchants, or for that matter anybody that carries out undersealing. I have personally had a vehicle undersealed before and I was very pleased with the results. (28,000 mile Mk3 always garaged and even that had some rust to deal with first)
The point I am trying to make is, that its no use putting underseal on metal if it’s already rusty. All you do is disguise the issue, potentially until cutting and welding is needed. If it’s done correctly then it can help prolong the life of a vehicle but Its worth highlighting the fact that it isnt a magic cure all and you need sound metal in the first instance, which is very rare of MX5s unless they have had exceptional treatment.
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That would suggest it’s ‘too late’ for the vast majority of MX5s since most don’t get sealed on day one. OR, that prior to treatment at a later point in its life there is a proper inspection including jet wash and scraping before sealant / inhibitor is applied.
No it does not, not all areas in Japan use it, but just for info the winters are far harsher than ours and the summers, all this is very easy to find out ,than guessing and picking comments apart, they are all undersealed to the same standard from the factory regardless of which country they are going to live.
Protection is the key and done correct and checked regular to having a happy life with your two seater , none of this is nothing new , we have seen it all before , its just a big circle , just a different make of car and better products to use than old engine oil.
M-m
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The only reason a mk3.5, or a 4, or no doubt a 5, is less rusty than a mk1 is that it’s newer. Mazda don’t care about longevity but do care about lightness, therefore they do little or no rustproofing as it adds weight.
If you’re going to rustproof your forever car, just putting underseal on it is not the solution. In fact it can make matters worse. You need to remove everything back to bare metal. This might look great as a base but is actually shiny rust. So that needs to be correctly treated, then primed, then protected. Cavities also need to be correctly treated by someone who knows how long to bung up the drain holes and how much the drain holes need to be enlarged after the protection has set. This is a week’s work. It is a bunch of horrible jobs to do. Depending on how much rust there is, expect to pay £700 for a mk4 and possibly thousands for an older car.
If you’re buying a car and see recent rough looking underseal, move on to the next car.
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It’s a filthy souls destroying job but someone has to do it and if a jobs worth doing we do it ourselves.
I’ve been known to resort to deox c gel and a pin
I’ve been quoted £350 to Dinitrol the underside of my 2004 NB FL. Does this sound a good deal?
too cheap for a thorough job!
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That’s what I was thinking but I’m in the North, could that be a factor?
Sounds too cheap to me as well.
Thanks guys, I’ll look elsewhere.
Had mine Dinitrolled by SW rustproofing in Westbury, Wilts. A 3 day job, fully documented with photos. They said it was the first 5 they’d done that didn’t need welding ! It was about £750 which included a check and top up after a year. If anybody quotes you much less then I’d look elsewhere. Mark at Total 5s give it a thumbs up, so I’m very happy overall
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You have to rustproof before any rust has started, otherwise you just seal it all in, pointless.
What you really need to do is keep your car dry garaged and don’t drive it in the rain. Probably best to just tax it April-September, store it over the winter and drive something else the other 6 months of the year.
I know this might sound a bit tongue in cheek, but I only really want to drive a convertible in the summer anyway.
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Can’t disagree with that. NMW is £9.50p/h. 3days at 7.5 hrs per day is £214. Cost of Dinatrol (input vat recoverable) say £100. Overhead to be absorbed (rent, bus rates, utilities insurance admin costs) say £120. Profit for business owner say £100 (he has to eat too). £534. Add vat at 20% circa £650. Doesn’t leave much fat in there for any cost I’ve missed off (which I will have) so it’s a competitive price and going lower for 3 days work isn’t going to be a runner.
Don’t laugh, but mine will be going into the garage for winter hibernation from late October. It will not leave the garage again until late March.
Obviously, I will use the down time to do all the little jobs on it that don’t require warm weather.
Noting wrong with using an MX5 during winter but, the lack of any additional underbody corrosion protection and NS-2R tyres make mine very much a summer car.
This is something you can all do yourself, but you need to get down and dirty for a couple of weeks for it to be done far far better than the up to £ 500 charge, including the products and equipment to do it, if i can get the standard i get on a drive , out side on axle stands, so can any body.
You lot are by far the best people to do it because of the attention to detail you will do that a garage etc that 100% wont.
Now is the time to do it so it all goes off quicker to be able to use them and enjoy this spell of good weather.
I will guide you through what ever you need to know to do this procedure “correctly and properly” as they will not go this deep,which i know it would be 1k upwards if you where using a genuine place , and i mean a proper genuine place, not the name that i keep seeing thrown around the scene, i have helped many in the back ground from getting ripped off with this process, and the worst bit is that after all the very hard work, no one sees it, but you know.
Take plenty of pics and document it all ,worts and all it helps in the long term for proof instead of ,taking someones word for it?
Something to read…
http://www.mazdamenders.net/forum/viewtopic.php?f=37&t=7520
M-m
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Brill. Very thorough job AND lots of great photos too. Thanks
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This has to be one of the most talked about subjects on the Forum, keeping rust at bay on our MXs.
I have a 2009 NC2 which looked brilliant up top but underneath a different storey. Dinitrol have a very good website and kits for different types of vehicles. Earlier in the year I spent a month preparing and applying the various coatings - RC900 rust converter, 4941 sealant and then the ML into the hidden areas. It’s a dirty ■■■■ job and I’ll probably have to revisit it every year to a lesser extent. I’m hoping to push back the rust clock 5 or maybe 10 years, who knows.