Paintwork

[patrickr90]

I'm new to the forum so hello everyone. Looking to buy a Defender 90 - pre-98 300 TDI. Currently looking at a Defender 90 and it seems quite tidy underneath. On the body, apart from some micro-blistering (which I've seen before when I had an old VW camper and I've read is a result of poor preparation and humidity during the paint job??) there are also a few bubbling areas - looks like rust underneath the paintwork?.

My question is: what parts of the Landy body are aluminium, what sort of corrosion is the bubbling and is it likely to break out in a mass of brown rust at some point. Or is it best left alone. Lots of defenders this age seem to suffer from the same problem - even ones a lot younger?

I think I can deal with the micro-blistering if it doesn't get worse.

Thanks

 

[dag019]

My question is: what parts of the Landy body are aluminium, what sort of corrosion is the bubbling and is it likely to break out in a mass of brown rust at some point. Or is it best left alone. Lots of defenders this age seem to suffer from the same problem - even ones a lot younger?

All of the upper body panels other than the bulkhead (firewall, part the dash/pedals mounts to) is aluminium. the bulkhead and chassis are steel and will rust.
The bubbling is likely to be oxidisation which creates white powder and does eventually rot through the panel similar to rust. this is likely to be what all off the bubbling in the paint will be. This is very easy to treat it is just a case of rubbing it back to bare bright metal, etch priming and repainting. it will last a long time as bubble slowly getting worse and then will split the paint work. Exposure to the elements does not really effect its progressions in the same way it would with steel, it is more aesthetic than structural. the biggest issue with the aluminium panels is the galvanic corrosion where dissimilar metals touch (e.g. a bolt goes through) this rots much quicker and you will find holes that are no longer round and much worse white powered corrosion around the area.

 

[patrickr90]

All of the upper body panels other than the bulkhead (firewall, part the dash/pedals mounts to) is aluminium. the bulkhead and chassis are steel and will rust.
The bubbling is likely to be oxidisation which creates white powder and does eventually rot through the panel similar to rust. this is likely to be what all off the bubbling in the paint will be. This is very easy to treat it is just a case of rubbing it back to bare bright metal, etch priming and repainting. it will last a long time as bubble slowly getting worse and then will split the paint work. Exposure to the elements does not really effect its progressions in the same way it would with steel, it is more aesthetic than structural. the biggest issue with the aluminium panels is the galvanic corrosion where dissimilar metals touch (e.g. a bolt goes through) this rots much quicker and you will find holes that are no longer round and much worse white powered corrosion around the area.

That's really clear, thank you! Are any parts of the door cills steel? I noticed there was some rust up behind a galvanised / stainless (possibly after market) checker plate below the door.

Since posting this, I've been put off this particular 90 by a local mechanic friend. He's steering me more towards something with a galvanised chassis because after a while patching the chassis just won't be enough. Is that true.. Presumably these galv chassis are like hens' teeth?

 

[Knappster]

Galvanised chassis are not uncommon but they weren’t fitted from new so it will be a replacement chassis unless someone has had the original chassis galvanised, which isn’t likely. The sills are aluminium if original, but chequerplate can hide a myriad of issues.

You will pay a premium for a Landy with a galvanised chassis but to get one fitted will be at least £5k depending on what else you have done or needs doing so it might work out cheaper in the long term.

 

[dag019]

That's really clear, thank you! Are any parts of the door cills steel? I noticed there was some rust up behind a galvanised / stainless (possibly after market) checker plate below the door.

Yes, the actual sill itself which bolts between the tub and the bulkhead is a piece of steel c-channel. you can get galvanised replacements (LINK). This is the part that the floor panel and seat box bolts along the threshold. It is then usually hidden by something else, either a sill panel - ali, chequers plate - ali, or some form of rock slider - steel. Put up some pictures if you are unsure and lots of advice will be given.

Since posting this, I've been put off this particular 90 by a local mechanic friend. He's steering me more towards something with a galvanised chassis because after a while patching the chassis just won't be enough. Is that true.. Presumably these galv chassis are like hens' teeth?

A galv chassis is always preferable, and these days a galv bulkhead as well, but that demands a premium price. to get one fitted yourself is a minimum of 5k, these days the chassis and bulkhead alone are over 3k, which doesn't leave much budget left for other parts and labour unless you do it yourself. there are enough with galv chassis about but they are certainly less common as if you have spent that amount of money it tends to be a vehicle you are planning on keeping. A quick look on ebay and FB marketplace will reveal some and the sort of pricing.