Salt corrosion

[kevin7799]

Hi all.

I'm a new defender 110 owner (1995) here in sunny Shaftesbury (Dorset). I'm very much a novice at mechanical stuff and have just started to have a serious look at the landy and when I removed the carpets in the tailgate section I have noticed there was a lot of white crystal type corrosion which has eaten through the ali principally around 2 bolts to a point where they are not really doing much and you can see glimmers of daylight and some sort of cross member underneath, 1 either side towards the row of middle seats. My conclusion is that it has been dipped in salt water at sometime. There is also the same pitted corrosion under the middle row of seats. So after an internet search I bought some SALT-X which neutralizes salt - hopefully, and sprayed it on last night. Has anyone else come across this, am I doing the right thing, the next part of the plan was to use filler, prime and paint. many thanks Kevin

[Ian J]

It's more likely that this is "galvanic corrosion" - which occurs when aluminium is placed next to steel, and an electrical current is passed through it (don't forget, the entire vehicle is the earth for your electrical systems).

Ian

[FridgeFreezer]

Ian's right, it's galvanic corrosion and happens all over Land Rovers where aluminium meets steel. It doesn't need a current passed through it, it generates its own as it's basically a very small battery all by itself.

[western]

see the link in this thread too http://forums.lr4x4.com/index.php?showtopic=58458

[Top90]

Without pictures it's hard to be 100% certain, but what the poster above says is more likely.

Some people say alluminium Land Rovers don't rust...

They do as they have steel parts, but they also corrode due to the reaction of the alluminium.

Galvanic_corrosion link and explanation if you need it.

[kevin7799]

many thanks to all for the quick responses, is the corrosion around these bolts possible MOT failure.

[Maverik]

The only way to beat it is to break the current path, i.e. paint it or insulate it from the steel.

Unfortunatly you will find ot all over the place.

But make sure you don;t insulate bits too well or your electrics will stop working!

can you specify what screws/bolts they are - photo?

[FridgeFreezer]

But make sure you don;t insulate bits too well or your electrics will stop working!

I think you'd have to dip the whole car in varnish for that to be likely, although the flipside is that the standard chassis return grounds are not the most reliable, hence why all my electrics are earthed back to the battery by an actual earth wire rather than rely on the bodywork.

[Maverik]

I think you'd have to dip the whole car in varnish for that to be likely, although the flipside is that the standard chassis return grounds are not the most reliable, hence why all my electrics are earthed back to the battery by an actual earth wire rather than rely on the bodywork.

Thought about doing this, have you just run a couple of general earth wires to the major earth point, behind dash, engine loom etc?

[FridgeFreezer]

I currently have a small marine twin bus-bar behind my dash for +ve and -ve fed by twin thick cables from the battery, most stuff then earths back to this point via normal black wires which I included in the loom when I made it. It really needs a tidy up and revamp though, probably moving to one of those busbar fuseboxes.