Restoration Meta Question

[JasonP]

At what point does a rusted body preclude restoration? The car I have does have rust - and some holes in the floorboards because of it - however, there is no rust near structural elements. The guys at the tire shop looked at it with me on the lift, and agreed.

I am really enjoying owning it, working on it, and learning it. However, I am afraid that I might finish up my "repairs/fixes" one day, and then find myself looking at a wonderful engine, transmission, interior, etc., with no body left. In my present situation, I see about 3-4 years until the car is completely restored.

My strategy is to halt the rust with that black "Miracle Paint," patch up the holes, and then later get a new paint job as the last thing on my list.

Everybody says to never bother restoring a rust bucket. I don't know if my car can be classified as a rust-bucket, but I have never done this before. This is my first car I have ever decided to repair/restore for the long term. I just don't want to be a fool and wake up one morning with thousands of dollars of restoration surrounded by orange powdery metal.

[oversize]

Well that's the million-dollar question isn't it!  Unfortunately the answer depends on many things.

How long are you going to keep the car?  Does it hold sentimental value?
Looking at it from a purely financial position, you'd have to look at it like an insurance assessor.  As soon as repairs cost more than 1/2 (?) the resale value of the car, it becomes financially unviable.

It also despends on what you can do yourself.    Paying a professional to complete the repairs is going to cost far more than DIY.  It also depends on where you live, as professional repairs in South Africa are more than reasonable.

Now the most controversial issue is how much rust is too much (which is what you asked in the first place).  Bolt-on panels aren't too much of an issue, as they can be readily replaced.  It's common for the doors to rust, but unfortunately it's normally the door frames and not just the skins.  Door frames are structural, even though they're a removable part.

Outer sills or rockers are common to rust but not too expensive to fix.  The sunroof frame is a common problem too, but sadly time-consuming to remove and repair.  Rust into the roof around the frame is also common and generally requires removal of the sunroof for an effective repair.

Floors are common and generally easy to fix once all the body deadener has been removed.  That job can be messy and a real pain.  Rust in the floor can incidate water leaks from elsewhere.

Rust in the rear quarters is common too and is often caused by leaking tail light lenses, boot seals, or rear windscreen leaks.  Not too difficult to repair.  Both windscreen seals can leak and rust around them is also common.  Impossible to repair without removing the screen first, to ensure all the rust is addresssed.

Perhaps the biggie is rust in the firewall.  Once visible you can be sure there's more lurking in places you cannot see.  Removing the wipers and have a look into the plenum (?).  Substantial rust down there is a big problem.  You can somtimes see rust coming through into the front inner guards which could also indicate major rust issues.  Why is rust in these areas such a problem?  Well it comes down to access.  Some places you simply cannot get into to achieve a repair.  And I'm not taking about just removing the engine and transmission.  There's often structural panels in the way.  I suppose they could be cut away and refitted later.....

Don't forget too that rust is a sneaky bastard.  Weld in a repair patch (and don't apply too much heat) and you may've done a great job.  You might grind it smooth, add seam sealer, high-fill and a nice coat of paint.  But what's happening on the other side of the repair??  The side you cannot see and cannot get access to???  Welds oxidize quickly and before you know it, the nice repair is rusting out again...

What's the solution?  On a new car they dip the whole chassis and the hidden areas (hopefully) get a coating of rust-preventers and paint.  On a restored car the best you can do is drill access holes to be filled with grommets later.  Don't forget to vacuum out all the shavings and metal fragments, as they'll begin to rust almost immediately.  And paint the edges of the hole.  With access holes you can get inventive and make a paint nozzle that'll spray in all directions and coat the back of your repair patch.

I've seen cars that I thought could never be repaired (even W116s) and yet repairs have been successfull.  I've seen cars built from almost no body parts that were salvageable.  But some of these cars would be worth big dollars when complete and that's the W116s downfall; they're just not (financially) worth much.  It comes down to how much is the car worth TO YOU and just how dedicated you're willing to get.

Note that the floor is a structural member; the W116 doesn't have a separate chassis like early classics from the 50s.

[Tony66_au]

Its really down to your skill level and commitment to learning new skills.

10 years ago rust scared me, Since then I have worked in a restoration shop and now nothing scares me anymore.

Own a good Mig, grinder and spot weld drill, buy donor cars or repro panels and get stuck into it.

Youd be amazed at the experience you gain sectioning or disassembling a donor car by taking it apart at the seams and repair is a reverse of the same process.

[ptashek]

Overisze an Tony66_au summed it all up really well. I was growing up in a body repair shop (although hands-off), and I have seen magic done to cars. Almost entire body panels fabricated from sheet metal without access to original press matrices or even another car to compare with. Cars built out of  multiple donors (halves, quarters - literally) coming out straight and within manufacturers specification. Budget and commitment is the only limit on your side, and skills on the workshop side - if you let someone else do it. If you have the space, tools and guts to do it yourself, I guess commitment is your only long-term limitation.

[Kjhall65]

Great question Jason.  I'm in the same boat as you and assessing whether it is worth restoring the 280SE I picked up as a parts car recently.  The car is in working order and a reasonable base from which to start. It also came with a spare motor and gearbox with 150k on them.

I have had a good look over the car and the only real rust problem is in the two front jack supports.  There are some other minor spots but the jack supports is what was putting me in two minds about a restoration.

Here is a pic of the worst of the jack supports.  What do you guys think? Is this a structural point or just the sill. Is the structural part further in where the jack support attaches to the structural parts of the floor pan?

[oversize]

I've seen far worse repaired before.  One of mine is the same and it'll be repaired.  Personally I'd start cutting and see how far it extends.  Then I'd bead blast the whole area and have a competent shop fabricate a new section.  You can buy outer sills on Ebay occasionally which are far cheaper than from a dealer.  Just watch out for freight fees.  No Licenced vehicle Tester in Victoria would issue a Roadworthy Certificate with outer sills like that and many would argue they're a structural component.  The inner sills are more important for strength and I'd be checking them thoroughly for tin-worm too.

[oversize]

Here's a link to a nasty one that still got repaired.  If this can be done then anything can be repaired!!!  I like to be thorough and I'm a big fan of blasting to remove all traces of rust before welding...  Using just a grinder doesn't cut it in my books!   

http://w108.org/forum/viewtopic.php?p=1075#1075

[Kjhall65]

Thanks oversize.  What is tin-worm???

The car was registered until about two months ago.  We don't need annual checks in the ACT any longer so I don't know the last time it went over the pits. I wouldnt even attempt a roadworthy like that....

[oversize]

Tin-worm's just slang for rust!      Get a decent grinder with a thin blade and buy a reasonable MIG.  Get some scrap sheet metal and practise, practise, practise.  I think the key is to spot and stitch weld as a continuous line generates too much heat and will distort panels....

[Kjhall65]

Just had a really good look at that link oversize.  What a monsterous amount of work that car is.  I can't believe how bad it was and someone was prepared to bring it back to life. Wow.

Are mig the ones with the feeding bar or is it a separate weld rod.  I guess you need to get one that can go to a very low amp so you don't cook the metal.  Do you need gas with it or just the welder.  I did a little bit of welding with an oxy acetal torch many years ago but this stuff it totally new to me.

Looks like a real,skill but one I would love to master.

[TJ 450]

I look at it this way,

If there's lots of rust all over the place, I would forget about it, and if rust is confined to certain areas only it's a possible restoration candidate.

I am always concerned about rust on non-removable panels such as sill, floorpan (extensive), firewall and around windscreens.

I consider my 280S a good project, because rust is limited to the firewall, scuttle panel and front windscreen aperture on the main body structure and some removable panels (doors). Firewall rust is minimal on this car and it is all localised.

Tim

[oversize]

One of mine was shut by the PO with moisture getting in through the sunroof.  It caused corrosion in all sorts of places (even ones that'd normally be ok) and for that reason it's highly likely to be a parts car.

Then there's the new one I just bought and I'll post pics to show just how much it's been neglected...

My 450SEL DJ is too far gone, but does have parts I can use.

So hopefully in the end I'll have 4 x decent 6.9s, which will keep me happy until I can't drive anymore (in about 40 years)! 

[oversize]

Just had a really good look at that link oversize.  What a monsterous amount of work that car is.  I can't believe how bad it was and someone was prepared to bring it back to life. Wow.

Are mig the ones with the feeding bar or is it a separate weld rod.  I guess you need to get one that can go to a very low amp so you don't cook the metal.  Do you need gas with it or just the welder.  I did a little bit of welding with an oxy acetal torch many years ago but this stuff it totally new to me.

Looks like a real,skill but one I would love to master.

MIGs use a wire on a reel and Argon gas as a shield during welding.  They're not too hard to master if you can get the settings correct; wire speed and amperage.  It's a fine balance between applying too much heat and getting good penetration, not unlike other different welding methods

[Kjhall65]

Thanks oversize, I'll have a good look into it all.

[wbrian63]

One factor that must be taken into consideration is the availability of donor parts and/or bodies.

In the UK, talented folks routinely recreate spectacular vehicles out of not much more than a pile of iron oxide. I think the very first tin worm was born in UK and is still eating cars by the zillions. Those folks will tolerate monstrous amounts of rust because there are no donor cars or parts - the donor population is in the same shape as everything else on the road i.e. there's nowhere in the UK that doesn't have a problem with rust. The climate and roads virtually guarantee that.

For a good example of what I'm talking about - read this... http://www.m-100.cc/forum/topic.asp?TOPIC_ID=4531

However, if one lives in the arid western sections of the US, one would have a virtual cornucopia of available spare parts and entire cars to choose from. Even old W116 cars have very little rust. I parted out a 6.9 that was a grey market car that lived most of its life in Arizona. The only part of the car that had measurable rust was the trunk (boot) and that was confined to the areas around the emblems. Much of the removable parts of that car now live on in another 6.9 in the Yucatan Peninsula.

The other consideration, of course, is the final prospective value of the vehicle, and whether that matters to you.

Even starting with a free car, you could easily spend > $10k bringing a badly rusted W116 (think minor firewall issues, new sills, floor pans, doors, and fenders aka wings) back to serviceable condition. Now, assuming that everything else is perfect (which is very unlikely), unless it's a 6.9, you'll never see your money back in your lifetime.

There are certain cars that should not be hapazardly altered (by blending pieces sourced from other cars) due to the reduction in value that practice causes. M100 Grosser cars would be an example of that. They are also hand made, which means truly no two are alike. Of course, unless you've got a small gold mine in your back yard, restoring a M100 car is out of the reach of most mere mortals.

One of the most common (in my experience) rust areas on W116 are the jack points. The body one sees where the jack points are exposed is merely a cover - it's non structural. The jack tubes and rocker panels (as I call them) are still available from MB for a reasonable sum of money. I think only the SEL versions are still stocked, SE owners will need to cut them down.

Oversize gives a good perspective on what problem areas exist and what it takes to fix them properly.

As others have said, the more you can do yourself, the cheaper it will be and you get to take pride in your accomplishments.

Regards