Swiss Cheese Sills - Structural or Not?

[SPendrey]

I need to replace my driver's side sill, and probably the other too. However, I'd rather not bother if I was to be told at the next MOT (2 days time) that there are other issues to be dealt with too.

My question, therefore, is whether I can drive to my MOT garage knowing the sill is holier than Mother Teresa? Are they structural at all? I expect a fail, and then drive home again knowing the full list of what needs fixing.

Thanks,

Scott

[Maverik]

Yes they're structural and yes I'd expect it to fail.

[Les Henson]

Sill is structure on a girly Disco . If you get a tug, then try to look all innocent and ignorant of the fact that your motor is about to snap in half :)

try to drive sensibly - indicate, wave politely at the old bill who are probably looking at you with distain and ready to throw the book at you. Resist the temptation to punt up the jacksy the Corsa driver that just cut you up The easiest thing to do is borrow my dog - the old bill won't come within a mile of a German Shepherd - their own ones tend to have a bite at every opportunity

Les

[SPendrey]

Thanks for those wise words Les! Not sure they're that helpful, except the first 6. But all good advice I'm sure :-)

Decided just to have a crack at it, and get a fresh MOT in about 3 months - about how long it'll take me to get the job done.

[Orgasmic Farmer]

If more than a couple of patches are needed then just get some proper box section steel and weld it in after cutting out all the carp. Plenty of archive examples of it being done on t'interweb.

[Bowie69]

There's a really good thread on here about doing just that, with 3mm box section.

YRM also make the parts you will need, for very reasonable money: http://www.yrm-metal-solutions.co.uk/epages/BT4822.sf/en_GB/?ObjectPath=/Shops/BT4822/Categories/Discovery_parts/Discovery_1_Parts/Sills

[SPendrey]

Got the box section, got all the gear, just not got much idea! Truth is I just need to get on with it, but with a valid MOT I just keep putting it off. MOT expires tomorrow, so I'm forced into it now. My welding skills are very poor, but will practice on some scrap first (worried about blowing holes through the remaining sill since the box section is twice as thick. Hoping I can learn to zig-zag a bit spending more time on the box section.

[Les Henson]

Practice a lot, but doing it on the bench is far different from lying on your back and doing it. Short bursts will help prevent blowing holes. Clean metal, good earth contact, will make a big difference.

Les

[JeffR]

You learn quit quickly, with old Disco, just how easy it is to weld rust... You will find that the floor above the sill will catch fire as good old LR decided to use equal weights of sealer and metal when building (I use that word with the utmost sarcasm and contempt I can muster) Disco's. What appears to be sound metal rather more often than not turns out to be "structural" paint....

[FridgeFreezer]

Two words: Eye protection!

Both times I've visited A+E it's been due to rusty bits falling in my eye whilst welding up someone else's rusty motor. One involved two hypodermics being used to dig the bits out of my eyeball, it's as much fun as it sounds.

[gavferg]

i solved all my sill problems using galvanised 100mm x 60 box section. Just cut the outer sill away completly then I slide the box behind the a and b post bits repairing them as i went. I bought new YRm body mounts i had them galvanised after lots of measuring and checking i then wleded them on to the box then cut all the inner sill away. Finally i put the box section back in and seam welded it to the body floor inside and out. Make sure the carpets out the seamsealer will melt and can catch fire also make sure your have got a good floor to weld too.The end result is Super Solid and all the mud traps are gone at last i would cap both ends and if you put the plastic cover back on using the plastic rivets try to use a silicon sealer to stop water getting in and it should last until the rest melts away.

my lastest surprise has been that the roof on my disco only has primer over most of it. try taking out the middle light and have a look all i could see was surface rust no paint at all. Roof liner out and a very thick layer of dinatol applied. i even sorted the headlining by replcing it with a freasher material of ebay.

i would now suggest doing this rather than chasing the rust moth a sthe sills rot from the inside out. once the rear cross member look dodgy ill do the same. box section costs washers compared to folded sills and theres less complicated welding. reboot floor dont bother with the reaplacment cross members you can get they rot within years even when well painted. i would use galvanised box section now.

and before anyone says: always grind away the galvanising on the welding area or you get a nasty case of welders flue as the zinc oxide is very good for you.

ive also been to have bits of rust picked out of my eye with a needle by a doc with awful bad breath. be very careful .

[katluke]

If your sills are totally rotted away like mine where and you need to fully replace them ,when you cut it all out be sure to leave the piece of metal in place that runs along the bottom of the door frame opening that holds the door seal in place.(Hopefully your sills won't be as bad as mine were). I used this to clamp the box section too as it puts the box section exactly in the correct place and at the correct height it needs to be fitted at. There is a few pics of how I done it in " Made a start " . Hth .

[SPendrey]

Ah yes, had a look. Mine is nothing like as bad as that (thank goodness). If it were, I'd have followed Les's advice in your thread and binned it! I'm half way through, old sill (outer and bits of inner) are gone, the box section is in place an welded up the outside. Yet to do the inside. I also have a couple of small patches to sort on the floor, but nothing too bad. Mostly the join between the rear wheel arch & rear passenger floor area.

[katluke]

How is the passenger side sill on yours ? I've worked on a few now and the passenger side always seems to be the worst, always a few other areas also needing a repair once you start stripping the sills out. It's not as daunting as it first seems to be repairing the sills , and the box section is a lot stronger job. If we didn't repair these old Discos with rust issues there would not be many left lol.

[SPendrey]

Haven't taken a serious look at the passenger side yet... but it isn't visibly bad. I'm sure the screwdriver will reveal the true condition soon. One side at a time though.

[SPendrey]

That wasn't so bad as I thought - although of course some areas were more tricky that others. Anyway, all sorted and MOT'd :-)

Passenger side is still original, and looks OK, although I suspect in 1-2 years I'll be doing the job on that side.

Mrs P made me laugh this week though. She drove it for two days while I was travelling on business (other car)... she said it's "very rattly". I checked, nothing wrong that I could see. So we both went out... she was changing from 1st to 4th and of course the gearbox was chattering until the revs picked up. Oh dear, lucky the other car is automatic I suppose!