Land Rover rear X member repair

[excossack]

Yesterday, I decided the rear x member on my Landy needed some attention due to rust...So, out with the angle grinder with a wire twist wheel and a flap disc.
All started well some surface rust removed.
Then I started on the biggest patch of rust. Attacked this with a twist wheel and got the worst off, then attacked it with a flap/grinder disc....Then it went from rust to a hole



???.!!! so decide to chop out the rust and patch up. I found a suitable bit of metal in the shed and broke out the welder using 0.8mm wire and Co2 I got the patch welded in.
After some welding and grinding flat and then coats of Kurust, zinc primer and some Matt black wrought iron paint, I ended up with this

 

[gav0994]

Nice tidy looking repair mate!

 

[mrcheese]

Nice repair. My 1991 90 seems to be OK (small repair where the X member meets the chassis rail), but my mates Td5 has rusted in the same place as yours on both sides. Looking at the trapped mud, I think it it is down to having the mud flaps fitted. The X member is not a great design when it comes to trapping crud!

 

[excossack]

Thanks, It didnt turn out that bad for the first time doing that kind of repair.
MrCheese, I think what happens is the spray and mud gets in the natural LR hole in the side of the chassis rail and gets spat up the tube and lands on the rear xmember and sits there munching on yummy fresh metal

 

[Chickenjohn]

Thats what we like to see! Butt welded repairs, and the end result is invisible. Good job :-)

Good idea now to get waxoyl/ your cavity wax of choice inside the member to prevent the new patch rusting out in no time- the inside where you have welded will be a bead of bare mild steel weld!

 

[mrcheese]

When I have been adding repair panels to my Discovery I have been spraying the the hidden side of the patch with zinc primer.

 

[excossack]

I need to find the hose for the waxoil gun. I was considering old engine oil?

 

[excossack]

and a butt weld, i thought was the best way to do it.

 

[mrcheese]

Not sure about old engine oil. When the welding on Discoshed is finished I need to treat the sills. Dinitrol? Thinned Waxoyl? Can I justify buying a compressor?

I have got to add some holes and flush out the crud in the sills.
I have not done it so far as it has been too cold to get it all dried out.

Butt welds are really satisfying as they are almost invisible when done right

 

[excossack]

Ive got the compressor and waxoil gun :-)
The other issue is, removing all the crud?
DO i accept that I will never remove the crud and just flood it with thinned downed Dinitrol/waxoil or try and hose it out and risk adding more water/dampness?

 

[mrcheese]

John,

Exactly my thoughts and dilema.

Paul.

 

[Chickenjohn]

If you have a compressor, you could blow most of the crud out with an air gun and then put the wax injection lance inside the member and blow air through it with no wax to blow more crud out. When no more comes out then you can connect up the tube of cavity wax and give it a good soaking.

Zinc spray, although a great idea inside a cavity is not enough as when you weld the final piece on some of the zinc is bound to get burnt off due to penetration of the weld into the inside of the box section leaving some bare steel. Hence the wax gun, or you could use a second schutz gun (kept clean for stone chip etc) to apply paint inside the member, then when dry, apply wax for maximum protection! :-)

 

[excossack]

The idea of blowing the crud out with the air line did appear in my mind, but, there are only a few 10mm (naturally) occuring holes in the chassis. Time to get undearneath and see what i can come up with.....mmmmm old hoover...