What you put in, you'll get back ten fold
***** THIS IS VERY IMPORTANT TO THE SITE AND HELPING YOU,OTHERWISE IT CLOSES AND ALL THIS ON LINE GARAGE IS GONE FOR GOOD*****

Greetings and welcome to menders, this site was built for every owner that might need her to help keep those bills low and also keep them on the road where they belong, she is run by very passionate enthusiasts owners for passionate enthusiastic owners, see her like a on line garage, there is a lot of tech stuff hopefully explained for everyone to use, if there is something you cannot get your head around, or you feel that there is a strong walk through guide missing that needs creating by one of us or from yourselves, please let us know, we are also on false book and youtube, which as short tech vids to help, and again if you feel there is a vid that would help please get it touch.
the menders is free, but like everything there is a cost to run things and bills( we are just happy its not a heating cost), so if we have saved you hundreds, please throw a small donation in the pot so we can keep on going to carry on helping others in the same way .

*** we are currently looking for a sponsor for this year, so if you have the passion and can see this sites worth to everyone , please get in touch and step forward to help***

And thank heavens that we are now on the way back up the brighter ,warmer longer days, "come on summer", and lets see those project builds.


M-m

Rustproofing a Mk3 / 3.5 Part 1

User avatar
Dewi
Regular
Posts: 69
Joined: Tue May 21, 2013 11:35 pm
Location: Pielandshire
Contact:

Rustproofing a Mk3 / 3.5 Part 1

Postby Dewi » Tue Jun 11, 2013 9:37 am

Part 1


When I was fitting the lower Eibach springs into my Mk3.5 Miyako, I couldn’t help but notice how little rust protection these cars have. At just over two years old my car was already showing signs of surface rust on the exterior outer edges of the front and rear subframes. Fortunately a peek into the sill & box sections with a torch showed there to be little or no rust in these areas at all so it was decided to keep it that way by injecting some Dinitrol into the chassis sections and sill areas.

It’s not a hard job to do on a relatively young car such as mine where no serious rust has had a chance to get a hold, but it is time consuming and quite messy. It is easily done on a do it yourself basis if you allow a few days and it’ll be a lot cheaper than sending it out to a specialist firm to do it for you. As a rough idea of cost I used:

6 aerosol “rattle cans” of Dinitrol 3125 cavity wax, and an extended application tube
3 large aerosols of underseal – I used Waxoyl u/seal from Halford’s
Rust converter / sealer of your choice – I used Hammerite No1
Degreaser (Panel Wipe) – you’ll get this from your local auto paint supplies shop
A couple of cheap paintbrushes, lots of old rags and containers to catch the drips in

Total cost of that little lot was around £90. Not sure how much it would cost to get someone to do the job for you, but done properly I can’t see there being much change out of £400. The nice thing about this job is that you can do it all without having to drill one single hole – Mazda have kindly done that for us. Pity they didn’t fill them with cavity wax as well but hey – we can’t have everything can we?

I own a decent compressor and was going to buy the canisters of Dinitrol that connected to my lance and airline, but I’ve used that method before on past cars and to be honest, because of the high pressure involved it atomises the cavity wax so finely that it just gets everywhere – which is what it’s designed to do of course but it takes ages to get rid of it from carpets, seats etc – everything gets covered in a geasy film. As my garage is attached to the side of the house, it even finds it’s way into there which delights Mrs. Dewi no end! So, this time in the interests of family harmony I used the aerosol cans, along with Dinitrol’s own little extension wand which works brilliantly, it gives a 360 deg application out of the end which gives more chance of treating everything that needs to be covered than a straight tube does. The added advantage of it over the lance I use on the compressor is that it’s a much smaller diameter - about 4mm compared to 10mm – ideal for getting the wax into the doors without having to remove the door cards. It also means you can do the outer sills without having to drill any holes – more of that later.

Before you start, it's essential that the car is completely dry, there’s no point in putting cavity wax over damp or wet metal, I’m lucky enough to have a nice dry garage, but the car had been out in a torrential rainstorm a couple of days before I started and was still a bit wet in places under the wheelarches and around the subframes. A couple of fan heaters under the arches for a few hours and good blow into all the nooks and crannies, rails with an air line (water trapped of course) soon had it all dried out, but if you don’t have access to these things then you’re best leaving it ‘til you’re sure the car has thoroughly dried out naturally. It may be an idea to take out the plugs (more of that later) along the sill sections a few days before starting, just to get some air flow through there which will help dry it all out

The easiest way to tackle the job is to break it down into sections, whichever suits you. I did: Offside front and rear first then nearside front & rear then boot – mainly because it was easier for me to jack one whole side of the car up and get the wheels off. Also better that way for running the wax into the sill sections and doors.

First thing you have to do after jacking the car up and removing the wheels – usual safety warnings apply here, the car must be securely supported, don’t even think about doing this with it supported solely on a jack – is to get the wheel arch liners out. This easy enough to do. However, there are loads of the little re-useable plastic push rivets that hold the front ones in, just when you think you have them all you find another bugger!. The centres of them have a cross head screwdriver slot, half a turn anti clockwise and the centre will pop up then you can simply pull the whole rivet out. You will break a few so buy some in for replacements. MX5 Parts charge about 65p each for them plus P&P but mine came from E.bay (where else?), they’re listed as Renault ones but they’re exactly the same as those on the MX5 - £2-99 for a pack of 10 and free postage! You’ll not get the front liners to come right out from under the arches unless you cut them to clear the spring, it’s obvious why when you see it. I chose not to do that and worked around it – it is bit of a nuisance but quite doable. You’ll also have to drop out the separate front section of the wheel arch liner and the large plastic cover from below the front of the car to gain access to the subframe These will come right out , and while they’re out of the way, it may be an idea to put new headlight bulbs in while you can get at them.
Last edited by Dewi on Tue Jun 11, 2013 11:56 am, edited 2 times in total.
User avatar
Dewi
Regular
Posts: 69
Joined: Tue May 21, 2013 11:35 pm
Location: Pielandshire
Contact:

Re: Rustproofing a Mk3 / 3.5 Part 1

Postby Dewi » Tue Jun 11, 2013 9:42 am

Part 2


The rear liners are a bit easier to remove but there’s a wire running through each one which I didn’t want to disturb so I did the liners to get them out, but they go back just fine afterwards. There are 3 plastic nuts and a few screws which are all that hold each liner in – again it’s quite obvious how they come out when you see them. Once they’re out you can start taking out some of the plastic bungs that will allow you access into the box section cavities. Starting at the front where the sill ends, behind the wheel liner you’ll find a the first bung, just get a flat bladed screwdriver under it and it’ll flick out but try not to scratch what little paint there is around the hole. There are a couple more inwards of the wheelarch, flick those out also. Now go under the car and you’ll see a whole row of them along the bottom of the sills. No need to get them all out – measure the length of the extension tube and take out enough that you can cover between the holes with the tube.

Those holes only get you into the inner sill though. There’s a diaphragm / membrane between inner and outer sill sections so to get to the outer one you’ll have to take off the sill finisher in the door jamb. That will expose several holes where the clips fit and you can get the thin Dinitrol tube down through them to apply the wax to the outer sill section. Without the narrow tube to get in there this is one of the only places you’d have to drill holes to accommodate the thicker lance had I used the compressor. You’ll find more rubber bungs behind where the rear wheel arch liner was and some more right up inside the wheel arch near the outer lip

Next step is to clean and degrease the exterior of the subframes, any surface rust can be wire brushed then painted over with the Hammerite or whatever rust converter you choose. Rejel – the suppliers of Dinitrol sell a spray on rust converter for getting inside cavities which have started to rust, but this is more suited to older cars where the rust has gotten a hold already. As my Miyako is still quite young I chose not to use this as there didn’t look to be any real rust inside any of the cavities of the body or subframes. A lot of people have the underneath of their car steam cleaned before starting the rustroofing procedure. It does get all the muck and crap off for sure, but the car can stay wet for ages afterwards and it’s my opinion that it’s not worth the effort of rustproofing a wet car – it’ll achieve nothing.

The degreaser I get from my local auto paint suppliers is called Panel wipe or Panel Degreaser. A couple of safety points if you do use this stuff. Firstly – ventilation and lots of it, the fumes are nasty so don’t spend too long breathing them in. Also wear tough rubber gloves and eye protection, and keep it off your skin it’s not a nice to thing share more than few minutes of your life with, but it will get grease & oil off anything and won’t damage paintwork in any way at all. Work it in with a brush into all the little corners etc but try not to get too much onto the rubber suspension bushes. It evaporates really quickly so it makes a lot less mess than gunk or similar products that have to be washed off afterwards. When that’s done the subframes can be painted with the Hammerite No1, or whatever you choose. I left the No1 for 24 hours to dry completely then sprayed the Waxoyl underseal over it, again leaving it to dry for 24 hours.

Now you can start applying the cavity wax to the box sections. I started on the subframes and worked outwards from there. This stuff drips all over the place so doing it that way means you’re not lying in it as you move about under the car. Common sense will show you where to apply it but the subframes are full of holes that can be used to access the insides of them. I found the best method was to push the tube in as far as I wanted it to go then squirt it in as I was pulling the tube back out. You need to get it well coated inside so don’t pull it back to quick – and not too slow that it causes a wax tsunami either, a bit of practice will soon get it right. The rest is just the same procedure for the sill and other box sections. A bit of time spent noting where all the access holes are before you start and making a plan of action is worth doing, the objective being to apply to the insides of all chassis members and box sections, take your time and make sure you get it everywhere.

Like I say, this stuff will drip out of everywhere you apply it – it’s made to be runny so that it reaches into all the corners and edges but because of that it does drip out and makes one hell of a mess. A few containers to catch it in is less wasteful as you can use what drips out to brush it onto to other more easily accessible areas.

When the underside and arches are done on both sides, pop into the boot and take out the carpet and the plastic liners – again they come out very easily once you’ve discovered how to remove the little plastic stud rivets – small, thin, flat bladed screwdriver in the little recess that runs around the circumference flick the centre up and the stud will come out – easy! The two big plastic studs that hold the carpet down just pull straight out. You now have access to the rear inner wings so get some wax into where the inner wing and outer wing join together and get some more inside the bracing for the boot lid – these are a known rust area on these cars as are the ones on the bonnet.

That’s it – you’re pretty much done. Leave for at least 24 hours and the wax will start to set so it'll be less messy and make putting everything back a bit easier. like I said at the beginning – not a hard job but it is time consuming and very messy. Not a lot of photos I’m afraid, I was covered in so much crap the camera was starting to look a bit second hand.

One last point worth a mention, a few days after doing this job you’ll need to make sure no drain holes are blocked with the wax as it puddles and sets. The main areas to check, being the door bottoms and the hood drains. If you go under the car and look in front of the rear wheels, about 6 inches in from the sill you’ll see a hole, one each side – about 10mm diameter. This is the drain hole for any water that runs off the hood so it must be kept clear. I used the extension tube that came with the cavity wax as it’s soft enough not to cause any damage but strong enough to clear any blockages. As it happened mine were clear despite having had a good wodge of wax put up there, but it’s always best to check.

Photos:

The access hole at the front inner sill section with bung removed. Note further hole to the right, this is a chassis box section. The brown stuff in the sill isn't rust, it's accumulated road dirt that's got behind the wheelarch iner
Car in workshop 2.jpg
Car in workshop 2.jpg (231.9 KiB) Viewed 17286 times


With the wheelarch liner removed the holes for the re-useable plastic rivets can be used for access into the engine bay chassis rails.
IMG_5792.jpg
IMG_5792.jpg (214.89 KiB) Viewed 17286 times


The rear wheelarch liner removed to reveal more holes (bungs removed) these allow access to the rear end of the inner sill
IMG_5793.jpg
IMG_5793.jpg (201.65 KiB) Viewed 17286 times


Under the rear wheelarch, you'll find 2 more holes each side. As can be seen there's not a lot of rust present in this car - yet!
IMG_5794.jpg
IMG_5794.jpg (331.59 KiB) Viewed 17286 times


Access to the outer sill is via the holes for the clips that hold the door step finisher in place. The Dinitrol small diameter tube fits in here perfectly
IMG_5799.jpg
IMG_5799.jpg (292.06 KiB) Viewed 17282 times



The rear subframe has many access holes that can be used to get the cavity wax inside - these are just a few of them
IMG_5795.jpg
IMG_5795.jpg (251 KiB) Viewed 17282 times


Same for the front subframe - lots of holes. In their defence Mazda have made it really easy to rustproof this car.
IMG_5797.jpg
IMG_5797.jpg (236.66 KiB) Viewed 17282 times


Not a brilliant photo but my glasses were covered in a greasy film by now so I couldn't see what I was taking. These are the access holes (some with bungs still in place) to the inner sill section.
IMG_5798.jpg
IMG_5798.jpg (273.15 KiB) Viewed 17282 times


The Dinitrol cavity wax brushed into the area behind the front wheelarch liner. It's very messy stuff, this was what was caught dripping out after treating some of the box sections...waste not want not! This is a low abrasion area as it's covered over by th ewheelarch liner so there's no need for underseal here.
IMG_5800.jpg
IMG_5800.jpg (130 KiB) Viewed 17282 times


The wheel arch liner back in it's rightful place, showing the finished subframe, the underseal was sprayed over the Hammerite No1 rustproofer.
IMG_5804.jpg
IMG_5804.jpg (241.47 KiB) Viewed 17282 times


D :)
User avatar
Mazda Mender
Site Admin
Posts: 15069
Joined: Tue Dec 06, 2011 6:18 pm
Location: Pie land, in the glen of Wiganshire
Contact:

Re: Rustproofing a Mk3 / 3.5 Part 1

Postby Mazda Mender » Tue Jun 11, 2013 12:21 pm

:handgestures-thumbup: :coffee:
M-m
The Disclaimer:-
This post is a natural product made from recycled electrons. The slight variations in spelling and grammar enhance its individual character and beauty and in no way are to be considered flaws or defects, the articles/answers/comments are provided for information purposes and they are not intended to substitute informed professional advice, I or mazdamenders.net cannot personally be hold responsible for any damage occurred from following this procedure or any injuries from it. Proceed at your own risk.


Mk 1 Eunos 93 black V.S II 1.8 ,
Mk 2 .1/4 Roadster 99 black & gold V.S 1.8 .
Mk 1 Eunos 90 1.6 soul red ..f/ build
MK 2.1/4 Blue V.S Roadster 1.8 99 ..
MK1 1.8 ,white import.. (Ashleighs)
MK1 1.6 yellow J ltd import.f/build
MK 1 1.8 black Tokyo Ltd..f/build


http://www.mx5oc.co.uk/ http://www.mx5nutz.com/forum/ http://miata.net/ http://www.autolinkuk.co.uk/
User avatar
RichW
Just Run In
Posts: 31
Joined: Fri Jun 28, 2013 3:12 am
Location: Goole, East Yorkshire

Re: Rustproofing a Mk3 / 3.5 Part 1

Postby RichW » Fri Jun 28, 2013 3:15 am

Superb thread - thank you very much for posting :)
Grew up on fast cars and bikes, bought a house and there it ended! GSXR 750 k5 and a Silver 2.0 Sport - both summer toys and long may the fun continue!

Image
drumtochty
Moderator
Posts: 429
Joined: Sun Aug 26, 2012 10:21 pm
Location: Auchenblae, Aberdeenshire

Re: Rustproofing a Mk3 / 3.5 Part 1

Postby drumtochty » Thu Oct 29, 2015 10:19 pm

Just foud this! Looks exactly like the same lack of rustproofing as the Mk4.

Just abut to check out my 2009 Impreza. I assume a bit better but not by that much!

Good work Dewi.
1999 Mk2 Silver
2008 Mk3 Copper Red gone
2018 Mk4 GT+ Red
Drumtochty Glen, Auchenblae, Aberdeenshire
CheshireMAZman
Posts: 1
Joined: Wed Jul 17, 2019 2:14 pm

Re: Rustproofing a Mk3 / 3.5 Part 1

Postby CheshireMAZman » Wed Jul 17, 2019 2:54 pm

I currently own a 2006 MX5 2.0 sport that I purchased in 2012 for some weekend fun. In the past I've used Waxoyl for the undercarriage section every couple of years. However speaking with a fellow MX5 owner they recommended a German brand called Dinitrol. I've just been doing some research online and found these DIY kits https://www.tiltrak.com/product-category/corrosion-protection/rustproofing-kits/ Does anyone have experience with this product range - is the protection any good? Also are the DIY kits easy to apply.
User avatar
Mazda Mender
Site Admin
Posts: 15069
Joined: Tue Dec 06, 2011 6:18 pm
Location: Pie land, in the glen of Wiganshire
Contact:

Re: Rustproofing a Mk3 / 3.5 Part 1

Postby Mazda Mender » Wed Jul 17, 2019 9:50 pm

Yes...i use them....very good stuff...
Read this it should help you..

viewtopic.php?f=35&t=6868

M-m
The Disclaimer:-
This post is a natural product made from recycled electrons. The slight variations in spelling and grammar enhance its individual character and beauty and in no way are to be considered flaws or defects, the articles/answers/comments are provided for information purposes and they are not intended to substitute informed professional advice, I or mazdamenders.net cannot personally be hold responsible for any damage occurred from following this procedure or any injuries from it. Proceed at your own risk.


Mk 1 Eunos 93 black V.S II 1.8 ,
Mk 2 .1/4 Roadster 99 black & gold V.S 1.8 .
Mk 1 Eunos 90 1.6 soul red ..f/ build
MK 2.1/4 Blue V.S Roadster 1.8 99 ..
MK1 1.8 ,white import.. (Ashleighs)
MK1 1.6 yellow J ltd import.f/build
MK 1 1.8 black Tokyo Ltd..f/build


http://www.mx5oc.co.uk/ http://www.mx5nutz.com/forum/ http://miata.net/ http://www.autolinkuk.co.uk/
User avatar
blackyb
Moderator
Posts: 1524
Joined: Tue Sep 17, 2013 8:41 pm
Location: Scarborough

Re: Rustproofing a Mk3 / 3.5 Part 1

Postby blackyb » Thu Jul 18, 2019 10:39 pm

I use dinitrol for the box sections and hard to reach places but stick to wax oil for the rest of the under body. I am lucky in that I work part time in a garage so access to a lift is easy. That said I touched up the underbody on my mx using my 3in1 tilting car lift in my own garage.
1993 1.6 Eunos Roadster (gone)
1998 UK Mk 2 1.6 (gone)
2003 1.8 SVT Sport (shouldnt have sold it)
1991 1.6 Eunos Roadster with a bit of bling.

Life is a journey, best travelled topless in an MX5!!

Return to “MK3”

Who is online

Users browsing this forum: No registered users and 5 guests