This begins a series where I'll explore some correctness and originality issues of the Pagoda or W113 cars. Let me state first that I'm not saying we should all only drive perfect specimens.  There are some very good cars that while less than perfect may suit ones needs.  It is just helpful to know the difference between various levels of authenticity.

Disclaimer: If you are considering the purchase of a car, there is no substitute for a direct pre-purchase inspection by a competent professional. The information contained here is for informational purposes only and will only touch on the subjects.

Originality is king when it comes to vintage cars. Not only does finding a 40ish year old car that has not been altered by numerous past owners add your enjoyment of the car; the more original features that you can substantiate the better when it comes time to sell your treasure.

Seasoned car collectors/investors have learned that a solid, sound, original body is the most important aspect of a vintage car. Mechanical rebuilds are straight forward and not costly compared to trying to correct a previously crashed or rusted car. One cannot throw enough money at a car with a bad body to make it right(or equal to a car with a great original structure). So with that in mind we'll start with how to tell how original the front body structure is. The factory made our job quite easy actually.

Most of the body was assembled by spot welding various panels together. Since most body shops used a different welding process to replace panels, one has only to look at the type of welds. The most prominent factory spot welds are just inside the engine bay along the tops of the front fenders. If these welds are not visible we know something happened after the car left the factory. Maybe a fender was heavily worked and body filler is covering the welds or possibly a fender was replaced. Due to the cost of labor to straighten a fender it was typically less costly just to replace a whole fender. In doing this the body shop most likely used a plug weld or simply mig welded the bottom of the two panels together(I've even seen them pop riveted!). The appearance will be very different than the factory spot welds.

Click on most photos to see the larger version.

The first three images below show factory original spot welds

Here the edge of the fender is smooth indicating repair work.

Also, the factory stamped the last three or four digits of the body number on the top left corner of the hoods. If this number is gone or differs from the ID plate then something happened. 

         
Obviously the two numbers above don't match telling us they belong to different cars.

Another indicator that something has happened at the front end would be an uneven hood gap. Since the hood is hinged only at two fulcrum points and must fit three dimensionally it is very difficult to get these right after a crash. The gap should be mostly uniform all around the hood. If it is not, look deeper.
 

Not part of the structure of the car but a treat to find none the less; a presentable, original firewall pad.  No one sells a new replacement that has the correct textured embossing.  What Mercedes sells as a replacement has a different finish; sort of a faux-leather crinkle surface.  Pictured left is an original pad.

Below is a photo of the replacement pad - see the difference?

Of course if one is doing a restoration and the existing fire wall pad is shot, outside of finding a good used pad there is no choice but to buy the new replacement. 
 

There are more body number stamps besides that on the hood.   This number is also repeated on the base of the hardtop, the boot box lid, the transmission support plate and on the data card(should be in the owner's manual pouch) at position #5(280SLs).

         
Above left is the hardtop base.                                      Above right is the boot box lid.

I've shown body numbers from several cars.  On an individual car the numbers should all match.
(note: sometimes this number is on the face-up side of the plate)

Runs, Sloppy Welds & Bare Spots

Ever been to a local car show and notice a beautiful car that is let down by a few runs in the paint?  We think, "this proud owner spent so much money restoring his car but got cheap with the paint job."  Well maybe we should not be so quick to judge.  If we examine a Pagoda hood on the bottom side that has never been repainted we find a large number of runs in the paint.  I'm pretty sure at least one of the primer coats was done by dipping the hood (if not dipped they were hung vertically to cure after spraying a liberal coat).  It simply was not considered important to sand these away before applying the color coats since most of the time the hood is closed.  We also find similar runs in the satin black of the underside of the trunk lid.  If you are doing a high point restoration I suggest that you not remove the runs if possible since this is another originality marker.  Factory replacement hoods come with a nice, uniform, run-free coating of satin black all over.  Below is a hood bottom that has been lightly sanded exposing the runs which exhibit as high spots.  

In most cases during the assembly of the body structure when two pieces of sheet steel were joined together, spot welds were used creating the neat row of dots (see front fenders at the top of the page.)  There are however exceptions such as the way the coolant expansion tank pedestal is affixed.  It has a row of what appear to be hand made mig-welds on each leg; basically rough bumps in the metal.  I recently had a technical manager from one of the top Mercedes tuning companies examining a customer's car for possible purchase.  Peering under the open hood he had said, "Oh this car has had some body work done."  I asked him to show me the evidence and he pointed to these very welds that we are discussing.  I had to show him five other cars that all had the same welds before he would take my word that they were indeed factory.  In an attempt at redemption he indicated that the welds were a bit rougher on this car than on some of the others.  Finally we agreed that maybe the workman on this particular car had one extra beer at lunchtime before completing these welds and we had a good laugh. 

Another interesting feature is the lack of paint in perfect circles in some areas of the engine bay.  These areas are where the various ground straps attach to the body.  The contact must be "metal-to-metal" in order to conduct current and these paint-less circles is how the factory achieved this.

More Numbers

I'm not sure where this "274" number originates from but we are going to do a bit
more automotive archeology and maybe answer that question.

Notice that the glove box and inner door panel all have the last three digits of the
production number (as seen above) written on them.

More to come........................