What can you do about undercarriage rust???

[e34.535i.sport]

Been doing a few jobs under the car recently, and the rust underneath has been playing on my mind a little. I've never had a car like this, and i plan to keep it for a LONG time as i am seriously in love.

THe rust isn't looking really bad, but its there and will probably get worse over the years if i do nothing about it, so i'm just wandering what can i do without spending a fortune? For example, the rear axle carrier is solid and mainly black in clour, but has definite rust around the edges. I'm planning to use something called 'ku-rust' which is supposed to turn rust into non-rust, and then paint over it with some undercarriage sealent type stuff.

Does this sound like a good idea or does anyone have a better way to protect it for the future? I'd love to replace everything now, but its not economically viable at the moment, so i'm doing it bit by bit.

Any advice or any methods you've employed to stop rust taking over would be appreciated

[Jehu]

You could sprout an oil leak in the lower timing chain cover gasket like i did and be coating the whole undercarrige with oil as you drive... ummm maybe there's a better way.

[e34.535i.sport]

Thats one way to do it!!!!! Hope you got it sorted quick enough?????

[attack eagle]

I'd honestly rather get rid of the stuff than use any of the rust fixer products.
But others say they are fine.

[g7syw]

You could sprout an oil leak in the lower timing chain cover gasket like i did and be coating the whole undercarrige with oil as you drive... ummm maybe there's a better way.

I got one of them - not enough to worry about but enough to keep everthing nicely lubricated :)

Personally, if it's possible to cut out the rusty steel and weld in new steel, that's the best option, all the other methods just slow the rusting process down. During my engineering apprenticeship, I was taught that nothing you can do will completely stop the dreaded metal worm from attacking... bugger!! :(

[e34.535i.sport]

I haven't go the kind of money to be repacing these kind of parts so i think i'll just try and slow it down, sand it off and cover it.

[525SEI BRIT]

use POR15 its the only thing that you can trust. this stuff is unbelievable!

to do it properly clean of the flak rust and bad paint first, then slap this on everything. waxoil is also good for all the box sections as you can buy it with a spray applicator. i do both just for pice of mind! http://www.por15.com/

another tip i discovered with my last E34, these cars like to go at the sills under the rear doors. theirs are 2 breather holes beneath the sill plates. rain water like to run under these plate in to the holes. (the later style plates had a rubber seal around the edge) a sika flex wall should stop the sills filling up. good luck, and get some rubber gloves!!!!!;)