Zagato wrote:

I REALLY would think twice about putting on any hard coat, despite treatments you will just be sealing rust in and it will continue to rot underneath . Once covered you won,t be able to maintain the chassis properly. I have had so many in that have had hard coatings of various sorts and underneath is just damp rot where moisture has got in from edges, chassis holes etc that have rusted where you cannot get a paint brush or for instance a drain hole edge where paint meets metal again where you cannot cover. It may look good for quite a few years but it will be rotting like hell underneath. Even brushing on old engine oil, waxoyl etc regularly would be better than half sealing in areas. It,s like squeezing spots on some of them, brown water just oozes out

I would totally agree with Zagato on this, I purchased a 1996 Defender 90 last summer and I am gradually bringing it up to a respectable standard. When I bought it the chassis looked pretty good and had been coated with a 'hard' black coating, not paint, what I am finding is either the coating comes off in sheets with damp corroded metal behind it, in some places, or it sticks like s**t to a blanket in others and is extremely difficult to remove to prepare the surface for any other protection.

My approach so far has been to remove the existing coating, clean using wire wheels, flap wheels, wire brushes, sandpaper etc, treat with Bilthamber rust converter, spray with Bilthamber high zinc primer and then paint with Paintman chassis black. My next step is to treat the inside of the chassis with Fertan ( http://www.fertan.co.uk/how_to_use_fertan.htm ), using a spray lance and compressor, to neutralise the rust inside the chassis. Finally I intend to spray the inside of any box sections with Bilthamber dynax S-50 and the outside of the chassis with Bilthambers clear protective wax so that I can see what is going on.

I have used both Dinitrol and Bilthamber products with quite a good degree of success on Classic MGBs and BGTs over the years but usually on new metal as the sills, floor pans etc have usually dissolved completely and had to be replaced, if it does not work on my 90 plan B will be a galvanised chassis and bulkhead.

If anyone has had any experience of using Fertan to halt existing rust I would be very interested to hear from them.

Best of luck with your project

mk1collector wrote:

If you prep the metal properly before painting with por15 then the paint seals the metal and rust and doesn't let any more rust develop. Read up on por15 website as that is exactly what it was made for.

I,m afraid companies claim a lot about their products BUT you won,t stop the rust 100%, you are just slowing it down largely by stopping oxygen getting to it and by the initial rust treatment. You are then just sealing It in and unable to address future rot. I used POR-15 twenty years ago on my Series II ground up rebuild, excellent stuff, rock hard, will never get rust through it BUT I only used it on a NOS military axle and the original rear axle as it was in good shape and would take years to rot through.

Careful of some of the POR-15 rust removal products such as marine clean etc. It's an American product where environmentally friendly regulations make it next to useless for serious rust. You really have to get rust almost back to bare metal for most of these acid convertors etc to work. They only work effectively on a thin layer of rust... not easy when you cannot get machinery in to all the nooks and crannies, top of chassis etc.

Have fun with your Series One, have you any pictures. I will put a pic up later of the military one I am working on at present. VERY NICE