Rustproofing a rust-prone car to use all year round?

[V-Force]

Hi guys.

I've recently bought a new daily - it's a 99 Civic Aerodeck VTi-S. It's pretty rare (13 left on the road) so I want to preserve it as best I can while still using it all year round.

I'm going to take advantage of the dry, hot climate we're getting at the minute and do it now to avoid any moisture getting sealed in. I've heard good things about Dinitrol and POR-15 products. Waxoyl I've heard can dry out and crack, letting water in and holding it against the car which will obviously make it rust faster. I should also add that I live on top of the UK's biggest salt mine so our roads are some of the saltiest in the country in winter.

I was also thinking of adding some cavity wax in the sills, chassis legs etc to prevent it rusting from the inside out - can I get an attachment to use with my compressor to inject wax into these sections? I work in the cavity wax facility at Bentley and we use this method on the Mulsannes, sadly I can't sneak the car in so I need to get something I can use at home! Also I'll need some seam sealer to seal back over the grommets that I'll need to pop out to get into the sills etc.

So can anyone recommend a decent underseal, cavity wax and seam sealer? Along with the methods and any tips that'll help. At work we receive the bodies pre-undersealed so I've no experience in that regard, only in cavity waxing with an air/wax lance. I was going to just brush the underseal on, and use an air-powered doohickey for the cavity wax. As for prep, should be pretty simple right? Wire brush the whole underside, get any dirt off, Kurust any surface rust and then brush underseal on? It's pretty mint underneath (needs a little welding around the front jacking points) so I want to do it once and do it right, then I can drive it through several winters without worrying about what the salt's doing to it.

Is underseal the best way or should I just use old engine oil? Seems to be a pretty popular method in Canada and they have incredibly salty roads compared to here, and it seems to work wonders!

Cheers!

[Ritchie]

Personally I prefer Bilt Hamber rust proofing products, have a look at their website for all the info.
You need an underseal gun kit with a pressurised gun, hose and long lance/tube thing.
Like this -

www.ebay.co.uk/itm/Professional-Rust-Proofing-Wax-Injection-Gun-for-Underseal-Waxoyl-etc-WS1/121506217427?epid=25017008851&hash=item1c4a55bdd3:g:FsUAAOSwZlZaJVCQ

I have one and it works well, and I just have a small compressor.
You just need to make sure the slits in the tip on the end of the lance are clear before you start as they get clogged up with old sealer and it won't distribute the coating evenly.
I clean mine out with some WD40 / Thinners and some wire plucked from a wire brush.
The guns that screw onto the 1L Cans are rubbish for undersealing properly as you can't get them into where you need to be, they are ok for applying on large flat surfaces though.
Any good quality seam sealer (U-Pol, Tiger Seal, Sikaflex) would be fine but personally I don't bother.
I like to make sure everything is as clean as possible, and even go as far as giving inner wings and return lips a wipe with panel wipe to give it as good a chance as possible to get a good hold.
Another tip is to warm the sealer in some hot water to thin it out a bit so it goes on easier, this might not be necessary if it's warm enough anyway.

[taurus]

I have used all sorts of products over the years. By far the best has been Waxoyl mixed 50/50 with clean new cheap 20W/50 engine oil. Get it good and warm and either spray or brush it on. The mix of Waxoyl and engine oil means it penetrates better than Waxoyl and it stops the problem of neat Waxoyl being too thick and sitting on the surface - then cracking off.

I've done a few that way, I get underneath every spring and recoat so it's not a fit and forget solution, but it works.

Very messy to apply however.

I've been down that salt mine, it's amazing underground when you see the machinery they've got down there.

[Vintage75]

Bilt Hamber!!

[spookies]

I'll second 50/50 waxoil and engine oil. After 30 years my old Ford is still as good as new under the thick black oily protective coat.

[chris y]

I'm using Waxoyl and engine oil too.
When put in cavities the oil never dries and soaks right into the seams, the Waxoyl gives it enough thickness to create a decent film.
I use on old food mixer to blend it well.

I blasted it inside of the sills I fitted to one of my Carltons, over the following days oil seeped out of the bottom seam, therefore I have absolute certainty that there is no dry recently welded metal where rust will start.

Most of us will have seen rusty cars that have had long running oil leaks, and the oil covered parts are completely rust free.
My Carlton was extremely rotten, but the drivers side front chassis leg had the benefit of a power steering leak long term and apart from the front few inches where it didnt reach was rust free.

[Deleted]

I have been professionally restoring vehicles for some 40 years now - in that time you learn what are the best products to use - The Dinitrol range is by far superior than anything else that I have ever used or come across - it has all the track records that you need - is straight forward to use and comes with some impressive results / guarantees - Use 4941 underbody wax for underbody areas & ML for cavity wax injection, they also do a product called penetrant which is a clear cavity wax and is ideal for door apertures / under bonnet areas - I also find that the product range is well priced & good value for money - link below

www.dinitroldirect.com/classic-car-restoration/

[ChasR]

I've heard that engine oil can actually be detrimental, well the used stuff can anyway. The blow by gasses in used engine oil, especially on cars which are tuned/worn or with simply a catch can on can actually have some nasty contaminents which can actually do more harm than good.

I've used Woaxoyl before and it's been fine. Bilt Hamber has been great and I've heard great things about Dinitrol.

[chris y]

Dinitrol sounds great, but its a bit expensive.

No need to explain to me about how much cheaper rust prevention is than rust repair, I agree, its a personal decision about the balance between affordability and how effective a treatment is and how often it needs to be done.


I also heard that used engine oil can be carcinogenic, not sure if its true but I use cheap new oil.

[taurus]

Old engine old is carcinogenic and can be acidic, though in general it does the job of denying oxygen to the metal so rusting becomes impossible. However as I said above - my mix is 50/50 Waxoyl and new cheap engine oil and that's what I'd recommend rather than using old oil.