Rust Advice

[ChrisInNashville]

Guys,

Here's my deal.   I removed the trunk rubber seal and found rust in the channel that holds the stripping.   The question is whether this is a repair that can be achieved with a scalpel (that is, spot sanding/repair with minimal painting) or will it require a hatchet (major sanding, major repaint).

Here's the history revealed in the attached pictures:

Original color green - last owner painted red (a $2,400 paint job in 1987).   Trunk channel had rubber seal on top of adhesive, on tope of red paint, on top of considerable original adhesive(!!) on top of original green paint.   Result is soft paint and adhesive "goo" that I'm removing with a wooden chop stick!   In addition, moisture clearly got under the soft/cracked paint beneath the rubber and was trapped.

Car got Ziebart in early 80's following some underbody rust repairs...other than this, rust is minimal.


So, the question is can this be fixed as a minor "spot" repair or do I have extensive work/paint ahead?  


Download Attachment: Lower Left Trunk Rust.JPG
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Download Attachment: Upper Left Trunk Rust.JPG
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Download Attachment: Left Channel Cleaned.JPG
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Download Attachment: Uncleaned Right Channel.JPG
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[Malc]

In regard to rust you really do not have a lot of choices. My personal plan of attack in regard to "your" rust and paint situation is as follows, other may go about it in a different way, and that maybe as good, but I have found that this works....

• Remove boot lid (Trunk lid)
• Remove everything from the boot (trunk).
• Remove tail lights especially LHS
• Mask off the seal channel,double up the masking tape. Then tape on some old blankets or similiar.
• Dry grit blast the seal channel, use a fine grit for a smoother finish
• Patch any holes, either metal or "bondo", up to you. [:p]
• use a good quality etch primer to paint bare metal.
• Finish in the appropriate colour

From your pictures the Lower Left Trunk Rust is the worst, with a possible hole in the metal.

If your careful you should not have to paint the whole car.

Using grinders, disks and other systems tends to remove metal as well as rust, and usually leave rust behind. "Paint on" rust converters convert from one form of iron oxide to another which has no structural strength!!

You would need a "syphon" type of grit blast gun and access to a compressor. In the UK Sealey Power Products make a good "DIY" gun SSG9EV2 I am using this successfully on the BMW Csi I am slowly restoring.
In the USA companies such as "Sandyjet" make them.

You need to wear protective gear when doing this, Googles and a dust mask at the minimum!  

Maybe this is abit over the top, but having "done" an MGA 8 years ago I have had no rust "breakouts" since and it is driven in all types of weather
HTH
Malc

[ja17]

Hello,
Malc is correct for a permenant repair. However cleaning the area up and coating it with something will keep it from spreading for a while.

Try "The Eastwood Company" (eastwoodco.com) they have an extensive line of restoration products, and information. Their catalog is great. They were also a contributing sponsor (products) for our last Ohio Tech Session. Be sure you mention the W113 Pagoda Group.

Joe Alexander
Blacklick, Ohio

[70chevelle]

I agree with malc, but you can remove rust with grinder disks, wire wheels, etc. and then use a "rust convertor" or "metal conditioner" as added protection.  It's your choice how you get back to "shiny" metal, and how you repair any holes that are going to appear.  I would not recommend using "bondo" to repair any hole.  Body putty should only be used as a skim coat to cover small imperfections in solid metal.  Seriously, body putty is like a sponge.  If bare putty is exposed to moisture, the paint will bubble quickly.  If you want a chance of the rust not returning, there are a few solutions.
           1)  Sandblast/grind to shiny metal removing all rust from top & underside of channel.  Repair any holes. (Weld, paintable seam sealer, anything waterproof)  Use a metal conditioner (usually phosphoric acid solution) to keep any rust you didn't grind or sandblast from spreading.  Spray with epoxy primer.  (wears like iron)  Spray paint.  
           2)  Instead of metal conditioner you can spray self-etching primer, and then paint.  The self etching primer has rust inhibitors in it, but it is not as durable as an epoxy primer.  Most epoxy primers can't be sprayed over etching primers, so you have to pick one way or the other.  

Either way will work, but the prep work is the most important.

70 Chevelle 13.7 @ 99.7
70 280 SL Silver/Black top
05 C230 Kompressor
03 Dodge Durango SLT

[Benz Dr.]

Here's a totally different take on this.
 If the trunk floor has serious rust problems remove the whole pannel and weld in a new one. It's quite a bit of work but probably no more than trying to clean up years of rust on a fairly thin part to begin with.
You definately want to remove the fuel tank before you even think about grinding or welding in this area. Cutting out and grinding will take up the most time but you have to remember that ANY part of this car has structural importance. This is a unit body car and even the trunk floor is critical in an accident.

How many of you are driving around with a front bumper renforcement that's little more than corn flakes? It's your responsibility as owners to put a safe car on the road, you know. I'd hate to ever read about someone from the group getting hurt or killed because their car crumbled up like an old tin can. Get under your car and really look it over carefully before you start driving this season. A few months of storage will make rusty areas become dryer than the surounding metal. Take a small hammer and tap any areas that look bad. Good metal will always have a metalic ring to it while rusty areas will go thud.

Safe motoring,

Dan Caron's
 SL Barn
benzbarn@ebtech.net
 slbarn.mbz.org

[70chevelle]

From the pictures, it seems that the rust issue is the slot that the weatherstripping fits in, and not the trunk pan.  Some good prep work, elbow grease, and reinstallation of the weatherstripping it should look brand new.

70 Chevelle 13.7 @ 99.7
70 280 SL Silver/Black top
05 C230 Kompressor
03 Dodge Durango SLT

[ChrisInNashville]

Thanks for the input.   After consulting my trustworthy mechanic and his recommended body shop, here's what I've decided to do of the following three options:

Option 1:   Strip the entire car to bare metal for $10,000.   Maybe when my 11 year old is done with college...

Option 2:  Repair the channel with metal which will require repaint of everything rear of the door for $1,400 to $2,000.   I'm OK with this, but I'm concerned with putting one more coat of paint on this fearing that the current layers will only deteriorate leaving me with only short term satisfaction.

Option 3:  Seal the rust, repaint the channel and a couple other "gimme's" for about $400.  

Conclusion:   Option 3 for $400.    Here's why:   All visible paint is quite good and I want to avoid messing that up.   Paint is limited to the invisible spot under the seal

This way, if I don't like Option 3, I'll pursue Option #2 and for the difference, I'm willing to risk $400.

Thanks for the guidance.   Everyone touched the various options in one way or another...However, I now have a new perspective on bondo  [:0]

[Malc]

Sorry about the Bondo thing  :oops:  I actually only use it to cover very small dents etc. I actually prefer the old method of "lead loading" which isn't as nasty as it sounds. Is water proof and doesn't shrink with age However it can be a long messy process!

I think Option 3 is the way to go I think if you catch it now then you should be ok

If anybody wants to know about "lead Loading" let me know
Cheers
Malc

[mdsalemi]

Gents,

A quick note about lead...

My restorer said he has seen many a $5,000 paint job ruined 30 days after finishing.  This is because the corrosive fluxes used in lead repairs leach out, and cause pinholes in the paint.  Just FYI.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[Malc]

Micheal,
Your'e right re "Lead Loading" but that's the whole point you have to do the job properly otherwise you end up with all sorts of problems...
I learn't the hard way  
If you do it properly then you don't get problems...
I once met a dealer in old cars... Whatever you had was shi*e whatever he had was gold.....
Ho Hum
Malc [:p]

[waqas]

Does anyone have any opinions about using something like POR-15 to coat undercarriage items (like trailing arms, axles, differential) as a rust prevention measure? Any alternative products out there that are more suitable for that purpose?

Waqas in Austin, Texas

[n/a]

I've used POR-15 with great success when I rebuilt my Saab Sonett, the car was disassembled when I found it, I sandblasted the chassis and coated it with POR-15, that was 7 or 8 years ago, and the car is as rust-free as the day I finished the work.

You want to use POR-15 on a surface that has some 'tooth' either sandblasted or wire brushed steel, a nice sanded piece of steel isn't ideal.

I know the instructions say you can put it right on top of rust, but I would grind/sandblast as much as possible.

-Lewis

66 230 sl 113042-10-016238
67 saab sonett II #43 of 258
00 saab 9-3 viggen conv
02 saab 9-5 aero

[Malc]

Hi Waqas,
Basic prep is most important, remove as much of the rust as possible, make sure everything is clean and free of oil and grease. I am not sure what POR-15 is, but I assume it is from somebody like Eastwood.

I have had great success painting suspension parts, axles and chassis with something called Chassis paint from a local company in Aberdeen called Spencers.

However you don't have to order is from them, you need to find a local paint supplier who provides paint for lorries (18 wheelers / trucks in US speak).
Usually it comes in "basic" colours but is tough as old boots and looks good. I have used it on the underside of many of my cars and it seems to hold up very well, despite the fact I live next to the sea and in Scotland they dump a lot of salt on the roads in winter!!!

I guess in Austin you will probably suffer more from sun damagerather than salt loaded roads in the winter!


HTH
Malc

[ja17]

Hello,
Any Rust repair must be done properly to last. Body lead, and  plastic fillers will not last if not used properly and applied to a solid metal foundation.

All of these fillers are lesser substitutes to good metal craftsmanship which has dis-appeared or too expensive to be used in most of todays restoration and bodyshops.

I have a factory new 190-SL front nose clip hanging on my shop wall(purchased in 1973). It is an entire front end consisting of 13 separate factory assembled  parts. The seams are hammer welded together and the seams are smooth and filler free inside and out. It is a real work of art. Your W113 body panels came from the factory the same way. Skilled metal workers welded and assembled the panels with no or a very minimal filler. Seams were nearly invisable inside and out.

A perfect repair with metal, pick hammered, hammer welded and filed would require no filler at all. These craftsman are hard to find or to expensive these days.


Modern substitutes like plastic filler will last if applied properly over a solid foundation. The same goes for lead work.

Joe Alexander
Blacklick, Ohio