Just had my 2007 L322 3.6 TDV8 in for a pre-MOT check and been told one of the failing points is the corrosion and weakened sections of the chassis/monocoque body shell along the beam-type sections beside where the exhaust runs on both sides of the FFRR....the pics show the right hand side (the other side is similar). This is on top of the usual rear sub-frame and rear sills etc needing done but i can do these, just need to find out if these parts of the body can be weld repaired? Anyone done this before or know how it could be done to pass MOT?...really don't want to have to scrap this beast! TIA

Click image to enlarge

Click image to enlarge

Click image to enlarge

Click image to enlarge

Click image to enlarge

I dont think it's illegal, yet, to make such repairs! I hope it remains that way too, but there is some doubt over the future, ref the 2024 dvla call for evidence! If you can do the other bits I can't see why you'd be doubtful of these bits though. Cut the rot out fully to solid steel and replace with same gauge steel, properly welded, non of that buzz, buzz, buzz continuous tacking ! Might need layers replacing where there's overlapping sections. Good welds don't need grinding away in areas like that.

Chris

No reason why it can't be repaired. Just look at the likes of Matt Armstrong and the repairs he does to properly crash damaged vehicles and bodywork.

That said, it tends to take an approach of chopping out the larger section as it was manufactured and replacing it in a similar manner to original.

You may be able to get a repair panel for that section. V8 or else ...

Thanks...

Happydaze was dreading it was illegal to repair that on the bodyshell...the next rick is finding places to put the axle stands and remove all the bits around those beams. Am thinking of going with cutting those beams back flush to the floor pan then welding in full box sections. Yes see what you mean re layers at the front end and back end. I've only ever welded way back in college days so this is going to be like starting from base zero! ...but have always been meaning to getting into welding

fisha thanks ive had a good look around for repair panels for those beam sections but can't find any, theres a good few for the outer sills and wheel arches though. am planning now to cut them out first to get a good look at what gauge steel and then start ordering up while getting me welding skills up on scraps!

Just don't cut ALL the rot out in one go, do it in sections, if you cut out that box section and the inner sills you might have problems with body sag....

Good luck...  Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand Sold
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Sold
2002 L322 Vogue 4.4 V8 Epson Green (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Cheers...ah see what you mean, i guess cutting out and welding in box-section, say in 300-500mm lengths at a time should keep it strong enough? ok so might have to weld repair the rear sills on both sides first so it keeps some stiffness for cutting out those beam sections...

Haylands wrote:

Just don't cut ALL the rot out in one go, do it in sections, if you cut out that box section and the inner sills you might have problems with body sag....

Good luck...

Personally I'd take the carpet out, it's not a hard job, just takes some time...

Front seats are very heavy... carpet is one piece and goes up over the transmission tunnel, because I presumed I would have to do it again I cut it both sides as far up as I could so the join would be under the centre console. If not you have to remove the console which is a fussy job and you usually break clips etc.... You could just take the front seats out, and the door opening trims, then fold the carpet back each side in turn...

If you take the seats out don't unplug the yellow airbag plug until you have removed all the bolts (4) as this will trigger a hard airbag fault (diagnostic tool needed to clear) and light on the dash, again, plug the yellow plug in before refitting. You need the ignition on to move the seat to access the bolts...!!

Good luck, welding upside down is awful, make sure no molten metal can drop up your cuffs and don't weld directly above your face.... You need to setup wire feed and amps control to find the sweet spot...

Good luck...  Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand Sold
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Sold
2002 L322 Vogue 4.4 V8 Epson Green (Fatty Offroader) Sold
-Click for Project Fatty off roader-

I think the welding element if the repair is not for a novice or well out of practice welder. Having said that I expect there might not be that much welding!

I imagine the rot is only at the bottom / lower sides of the chassis rail, so why take the whole chassis section out? Some investigative grinding or needle scaling should reveal the extent of the rot. If it just the bottom section a suitable folded u section could be acquired to fit. I'd get the air tank out of the way, it looks dead anyway ( I think its the air tank!). Fully cleaned up and prepped it's an easy weld up. Hopefully we'll away from the floor and thus carpets etc.

Surface rust can be ground away, treated and painted. Only rotted through and / or heavily pitted ( thus about to rot through) areas needs to be replaced.

Chris

One has to ask if its viable to save? Ill guarantee the rust will be 200% worse than what you see in those images! Once you've started, I suspect you'll be chasing your tail around many many more areas of corrosion before your finished! There can't be a lot of value left in a car of that age either, so is it not worth buying a good (southern) car without the rust problems you see in Aberdeen cars?
Sorry to be a Debbie downer 'n all' but sometimes its better not to start projects like this without taking stock first sir...