Thread: Defender Chassis Rust and Paint Advice

Doesn't really look that bad to me. Penetrol is your friend here. you can either paint a coat on after removing any loose stuff, then paint with top coats, or paint on a coat of your favourite oil based black chassis paint with 10-15% of penetrol thoroughly mixed into the paint. (two coats of that)
That should do it.
Don.

I just give it a good cleaning, a rub of a cloth with diesel then standard undercoat used for gloss paint. Then when the undercoat dries I just slap on the gloss paint. Putting it on with a brush gives you a really good thickness of paint.

Wattyl Killrust works for me.

You could paint on some rust converter, leave it a day for the acid to work, wash it and then slap on some Killrust with rust converter in it. Then spray oil when it's dry.

You might want to look at this write-up DEFENDER2.NET - View topic - Corrosion Prevention Guide! by a Defender rust prevention guru in the UK where they use salt on the roads in winter. His product of choice is Dinitrol which unfortunately is not currently available in Oz although there is a guy in Melbourne who has the local distribution licence and is looking for stockists. Landrover Defender | Rustproofing | Underbody | DINITROL

When we first got my son’s 2003 Defender 90, I looked underneath and saw what looked like a build-up of leaked oil and red dust from up north (yes there is an oil leak …..or twenty!). I sprayed degreaser on and started scraping. I soon discovered that it was actually a bitumous like coating which I now believe to be Dinitrol 4941 or a similar product as the previous owner worked for Land Rover in the UK. It has done a pretty good job of protecting the undersides as there is no rust there except in two spots in the rear cross member (you can guess where). I now need to patch the bit I scraped off and I plan to use WURTH Under Body Seal as it appears to be similar to Dinitrol 4941 and is available in Australia. Apparently, Wurth used to supply to the Australian car manufacturing industry .…when we still used to make cars here.

Following this thread. My 2012 Puma has been on the beach at some point in its life and the underbody looks a lot worse than yours! I’ve read some opinions that say even with treatment, the corrosion continues anyway, albeit hidden and less unsightly. I’ve also had advice just to keep it clean and not worry about it too much. Not sure what to do. At the stage, I’m planning to hang on to the vehicle for a while and I don’t want it to disintegrate but at the same time there’s probably other priorities for my finite time and budget. Ah anxiety, my old friend.

Definitely keep it very clean, particularly inside the chassis.

Originally Posted by DiscoMick

Definitely keep it very clean, particularly inside the chassis.

Yep pretty fastidious with giving the underbody regular soakings with the pressure hose, including inside the rails.