Car restoration or wanting to prolong the life of your Mazda MX5 requires some kind of rust proofing. As with every industry and market sector, there are a number of different brands and product types on the market for rust proofing cars, so knowing which will offer thorough and guaranteed protection as well as ease of application, can be a challenge.  A product range that offers a three step approach to rust proofing is a start in making the right choice. Taking to the Internet and reading through various forum posts related to rust proofing your particular make of vehicle is also very helpful, as too is reading reviews posted on product websites.These are great ways of making an informed decision before going to work on rust proofing your car.  Use the internet to check product availability and remember, cheap is not always best! 

In this article we discuss the use of the Dinitrol range of rust proofing products to protect the undercarriage of a Mazda MX-5 to add more years to this popular classic car.

3 important steps to rust protection

• Convert all signs of rust to eradicate it completely,
• Apply a rust protection coating to the undercarriage, sills, wheel arches, side-panels and cavities,
• For added protection, apply a sealant coating.

Steps to rust proofing a Mazda MX5 using DINITROL

1. Step into your grubby clothes, jack-up your car and remove all four wheels 

   

2. Remove all under body protection to gain access to the undercarriage for a full rust proofing - remove the plastic arch liner held together with pozidrive screws. Place all black plastic clips and screws that you remove and place into a bowl so that you can readily replace them when the job is complete. Remember to also remove the plastic under-tray covering the fuel filter (driver’s side, in front of the rear subframe) and the front engine under-tray.
3. Give your car, including the undercarriage a thorough jet wash to remove all traces of dirt and caked-on mud. Pay attention to the lips of the wheel arches and the point where the front arch meets the body-shell. If you have mud-flaps, remove them too for full access. Mud which finds its way into awkward corners holds onto moisture and it is this that initiates the onset of corrosion so be absolutely thorough in your preparation.
4. Leave your car to dry-off thoroughly - it is advisable to do the wash-off one afternoon, with a view to complete the rust proofing the morning after. The car needs time to dry off, a good few hours I guess. I left mine overnight.
5. Remove the sill guards - 4 screws each side which will need removing.
6. From the front edge to your rear wheel arches, lever off rubber plug which is about 30mm in diameter - put it in a container for safe keeping and put back once rust proofing job is complete. This should now give you full access to the sills, and using a torch will enable you to detect any surface rust, which will need treating before rust prevention applied.
7. Take Dinitrol RC900 (which is part of Dinitrol Mazda MX5 rust proofing kit - details of which are at in the last section of this article) and apply using the long wand. You need to get a good covering of the product on all the inside surfaces. By threading the wand in through the holes then pulling it out slowly as you squirt ensuring you get a good coverage. Go in through the wheel arch hole too and apply liberally.
8. The frame rails to the underside of your car is the lowest point of the chassis so often takes a bit of a bashing from speed bumps. Check the whole of the underside thoroughly for areas of damage. If there are dents and surface damage, there is likely to be the onset of rust too. There are a number of access holes to the floorpan through which you can pass the wand from Dinitrol RC900 and apply another liberal covering.
9. Now using the regular spray nozzle of the Dinitrol RC900, and apply to any area of bare metal where there are signs of rust.
10. Check the front and rear ends of the car, the boot floor - looking from underneath, treating any bare metal showing signs of rusting.leave anything that’s clean metal.
11. Allow around 6 hours for the rust converter to work. RC900 is quite runny on application but dries quickly.

Application of Dinitrol 3125 cavity wax rust prevention

1. Dinitrol 3125 cavity wax is designed to run into all the cracks and joins in the metalwork including the seam of metal that runs along the bottom off the sill. Again use the Wand to apply the rust proofing to the metal surfaces for all but the body of the car. Apply the same technique as you did when applying the rust converter to all the sills, the insides of the frame rails and through the bunghole in the rear arch. You can go in through the bonnet to get access to the front end of the two frame rails running right up the front crossmember.
2. Make sure all internal surfaces are covered with the cavity wax. Poking the wand all the way in through a hole, then spraying as you pull and twirl will ensure you apply good coverage.

Underseal with Dinitrol 4941 rust proofing

1. Dinitrol 4941 is used to protect and seal all the external areas. Easy to apply evenly and thinly, drying to a tough, thick, rubbery under-seal. Start with the wheel arches making sure you get plenty of coverage in all the corners. Get the can up in the arch and spray back into the lip of the arch ensuring you also get the inside edge of the front wings and along all the seams in the metal – seams are where rust often starts.
2. Replace the rubber bungs into their holes and seal them in with Dinitrol 4941 - the viscosity of the product and the fact that it hardly runs means you will get a an even, factory-looking coating over all the areas you have applied it to, without it going everywhere you don’t want it to.
3. Apply to the boot floor and the around the frame rails, to the the frame rails at the front, the inside of the front wing, and the areas beneath the footwells.
4. Make sure you apply a thick covering on the whole of the underside particularly to areas where the previous underseal had scraped away on the frame rails. Spray outwards onto the inside edges of the sill seams, and to get the areas further into the centre of the car.
5. Leave to dry out over night before putting your car back together again allowing enough time for the underseal rust proofing wax to cure with a hard ‘skin’ on the surface (although if damaged it self heals ‘flowing’ into the gaps).

RC900 Dinitrol rust converter will stop the spread of any of the light rust that was present, and the cavity Wax will stop any more occurring. This product also works well for painting rusty metal – I’m in the process of rebuilding my brakes also, I wire brushed them then primed with the rust converter– they painted up lovely once it had worked its magic. The chemical reaction changes all the rusty metal to a different chemical compound that is inert.

Dinitrol rust proofing kit design specifically for the Mazda MX5 includes the long Wand fitting, a number of plastic bungs - on some cars it would be necessary to drill some access holes which would need sealing afterwards although the Roadster has plenty of access holes dotted all over the body.

DINITROL Mazda MX5 rust proofing kit

The DIY Rust proofing Kit contains all you need to protect your Mazda MX5. 

Kit contains: Dinitrol 3125 Cavity Wax 500ml Aerosol x 3, Dinitrol 4941 Underbody Wax 500ml Aerosol x 2, Dinitrol 4010 Clear High Temperature Wax 500ml Aerosol x 4, Dinitrol RC900 Rust Converter 400 ml Aerosol x 1, Extension Spray nozzle 600mm long, 10mm Black plugs x 50, CANGUN x1

• DINITROL Cavity wax will not crack, chip or peel and is designed for application to internal and external surfaces of vehicles
• The product is particularly suitable for use on old vehicles where corrosion is evident, such as the underbody.
• Drip free application. Dries to leave a brown, hard, waxy film
• DINITROL underbody wax is a corrosion preventive coating which provides long term resistance against corrosion and abrasion, even under extreme conditions
• Dries to leave a tough elastic waxy protective coating
• DINITROL Rust converter actively converts rust on substrates into a stable organic iron complex. This product will penetrate rust 7-10 times deeper than standard rust converters

Genuine products supplied by Rejel, the official UK Distributor for DINITROL.