Originally posted: 12 November 2020
Last updated: 14 October 2024
Creeping rust is one of the biggest problems facing owners of classic and modern Volkswagens, but there are things you can do to treat rust, and stop rust forming.
Noxudol is one option available to vehicle owners, which is easy to use and really effective.
Here’s a quick guide on how to use Noxudol to treat existing rust, and prevent rust from forming.
A Bit About Noxudol and Rust
Two things are required for rust to start: water and oxygen. There’s no way of stopping oxygen from getting to your vehicle’s metalwork, but you can help prevent water or moisture in the air from getting to metal surfaces.
There are various products on the market, but recently we have started using Noxudol as well as Ankor Wax.
Noxudol probably isn’t a brand name you’ve heard of before, because it’s traditionally only been available to vehicle manufacturers. That’s all changed now, though, and you can get a great range of Noxudol treatments available here at Just Kampers.
Noxudol has been developed in conjunction with Volvo to offer environmentally friendly options for rust-proofing which also allow you to work in an emission-free work environment. They’ll also leave your vehicle odour-free after the wax has been applied, which is great.
Both the Noxudol 300 and Noxudol 700 formulas are solvent-free, which is great for the environment and requires less safety equipment during application.
On the other hand, Noxudol 900 does include solvents in the formula, which helps it to dry and set faster.
How to Use Noxudol
A while back we picked up a 1970 T2 Bay Westfalia for the Win a Camper competition we ran with our colleagues over at Just Kampers Insurance.
The Bay had undergone a sympathetic restoration and been fully repainted, but it had not been rust-protected.
Luckily, this gave us the perfect opportunity to trial Noxudol 700 cavity wax and Noxudol 300 under body wax!
The theory is very simple: by coating the inner structure or underbody with a layer of wax, we could prevent moisture from making contact with the metalwork, which would then stop rust from forming.
Here’s how we treated the metalwork on the T2 Bay:
Step One: Clean Your Vehicle Before Applying Noxudol
It’s important to clean the underside of your vehicle a couple of days before you want to apply your Noxudol.
Giving it a good blast with a pressure washer will make sure you’re working on a nice clean surface, and mean you won’t be trapping any mud or dirt against your vehicle’s body with a layer of wax.
The reason we suggest cleaning it a couple of days before you apply the Noxudol is that this will give it enough time to dry nicely – it’s not easy to get under your vehicle with an old towel to dry it off after you’ve cleaned it!
Step Two: Preparing Your Vehicle for Noxudol
We started by removing the interior trim panels from both cab doors, the tailgate and the sliding door. It’s best to use a trim removal tool to get the door panels off, so that you don’t damage them or your doors. Luckily they’re pretty inexpensive and useful for a lot of different things!
Once the door panels were removed, we cleaned out any dust and debris from the bottom of the doors and checked to see if they were dry. It’s amazing how much stuff manages to get in there despite the door panels being there.
It’s also a good idea to take a look at the plastic membranes inside your cab doors, to make sure they’re not damaged and are working properly. These thin sheets of plastic stop any water which seeps into the inside of your cab doors from coming into contact with the door trim and damaging it, so they’re really important.
You should also check that the drain holes in the bottom of your cab doors aren’t blocked, and that the cavity which is designed to collect water isn’t rotten or rusted.
Step Three: Rust Proofing Internal Surfaces
Luckily for us, the insides of the doors on the T2 Bay we were working on were in great shape, so we used Noxudol 700 cavity wax to treat them.
This offers good penetration and will work its way into cavities and joints more easily than other rustproofing treatments do. Noxudol 700 is available in cans designed for low-pressure spraying with compressed air and a Schultz gun, but it can also be brushed on.
We also stock an Noxudol 700 as an aerosol which is ideal for use at home if you don’t have a compressor and a Schultz gun!
Using a probe on the Schutz gun we then applied a thin layer of wax to all the internal surfaces that we could access, taking advantage of any factory-made holes to get to the inner structure.
The wax is clear, so it’s hard to see in the pictures, but once done we repeated the process several times. This allowed us to build up layers of wax and ensure maximum coverage.
In a couple of areas, the probe was too large to access, so we used the aerosol version instead. It’s supplied with a handy straw which was easier to use for these hard-to-reach places.
Step Four: Rust Proofing External Surfaces
Once it was time to tackle the underneath of the camper, we put it up on the ramp in our on-site workshop which made it much easier to access everything we wanted to treat.
The job isn’t impossible without a ramp, but be aware that it will likely take you much longer and you’ll want someone with you to help you out and pass you things to speed the process up.
First we treated the internal surfaces of the outriggers/jacking points, all the cross members, the inner and outer sills, and wherever we could gain access.
Where we could we pushed the probe in as far as possible then slowly drew this back as we sprayed the wax ensuring as much coverage as possible. Take your time, and remember that you might have to think laterally about how to access the parts you want to treat!
To protect the paintwork and prevent any overspray from contaminating the finish we masked the sides of the van and sheeted over the top. This may be a little over the top, but this was a camper we were working on to give away in a competition with Just Kampers Insurance, so we wanted to make sure it looked its best and lasted for years to come.
At the least, we’d recommend masking the lower edges of the sills etc. If you’re careful you should be OK, if you do get wax on the paintwork it can be easily cleaned off with white spirit.
Step Five: Rust Proofing the Underside
With this completed we then turned to the underside. Our van was a Texas import so was solid underneath but had a light coating of rust/dust and the odd termite nest. We cleaned the underside with a wire brush but also found a stiff hand brush useful for this. Any areas of oil or grease on the underside were cleaned using Renox degreaser, which works brilliantly.
For the underside we were using Noxudol 300. Like the 700 we used earlier, this treatment repels water and moisture, as well as offering good protecting against road salt used for de-icing in the winter.
Noxudol 300 is also available both in a can or an aerosol, and we used the Schultz gun with the can again, with a spray nozzle.
The underside of the van was sprayed, taking care not to cover any mechanical components. In critical areas where overspray will cover certain parts, you can decant the coating into a pot or tub and apply with a brush which will be much more accurate.
All areas were covered including under the wheel arches, and we used several thin layers again to make sure everything was properly coated.
Note: Areas Not to Coat with Noxudol
There are some areas of your vehicle that you need to avoid when treating the underside, as getting cavity wax on them will cause damage or simply break them.
These areas include:
Sensors – Make sure any sensors and connectors under your vehicle are covered by masking materials to avoid damaging them.
Suspension – Do not apply on moving suspension parts such as shock absorbers etc.
Brake components – Don’t apply cavity wax to any brake components, and be sure to remove any immediately if it does get onto your braking system by accident.
Exhaust system – Make sure not to apply on exhaust components or heated surfaces.
Air intake – Don’t get cavity wax on your air intake, if your vehicle has one.
Powertrain – Make sure not to apply on powertrain components, such as the engine, transmission, drive shafts, differentials, etc.
Noxudol advise that these areas are covered in masking materials, like tape and plastic sheeting, to ensure that they don’t get coated in cavity-wax while you’re treating your vehicle.
You’ll also need to make sure you’ve removed all masking materials once you’ve finished applying the cavity wax, so that you don’t damage your vehicle by driving off with these components covered up once the Noxudol is dried and set!
Step Six: Allowing the Noxudol to Dry and Set
Once done the van was unmasked and left for several days so that the treatments could set.
Noxudol 300 and Noxudol 700 are solvent-free, and the drying period starts 24 hours after it’s applied.
It can take 3 to 7 days to fully dry, depending on the temperature and moisture levels around your vehicle while it’s drying.
It’s recommended that you don’t drive the vehicle until the Noxudol treatment is fully dried to ensure that it’s properly protecting your vehicle.
If you need a quicker dry time, we recommend using Noxudol 900 instead, as this can be used immediately after application. Note that Noxudol 900 does include solvents in the formula, though, so you’ll need to take extra precautions while you’re applying it to keep yourself and anyone you’re working with safe.
A Quick Summary
Overall we found both the Noxudol 300 and Noxudol 700 sets really easy to use and super effective, which is fantastic.
It’s really important to protect your vehicle’s underside from rust, and applying a cavity-wax like Noxudol is well worth the investment of time and money!
Video: How to Apply Cavity Wax
We filmed a quick 3-minute video on applying cavity wax while we were working on our 1956 VW Beetle, to show you how it’s done.
We used Noxudol 900 and Noxudol 700 on the Oval Beetle, as well as Morris Ankor Wax.
