Casting Number on Cyl Head Defaced

[ctaylor738]

Getting ready to pull the head to correct the smoke screen at start-up, so I checked the casting number (136 016 "08" 01) to be sure that I get the right gasket.  The important digits have been carefully defaced, looks like with a punch or chisel.  Still barely readable as an "08".  

But why would anyone do this?  Has anyone seen this before?  Does it have some meaning in the machine shop world?  BTW, it is a 9.5 280 SE/A head.

Chuck Taylor
1970 280SL #14076
Falls Church VA

[Naj ✝︎]

Chuck

Have a look at the chart on the first posting here:

http://index.php?topic=1338,head

naj

68 280SL

[mdsalemi]

Chuck,

Some rebuilders alter, change or obliterate numbers on the castings to signifiy that the part has been rebuilt.  Don't ask me why they do this, they could just keep track of serial numbers, casting numbers, etc.

Alternatively it may have been altered in some way during a rebuild and someone changed things to let you know that it isn't the same as the casting number that was obliterated.

No I don't understand this but I know it's true.

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

[ctaylor738]

Exactly.  It's clear that the head has been off because it is much cleaner than the rest of the engine.  Maybe it's a warning to the next machinist that it has already been rebuilt.

But why the critical digits in the casting number?  And it's not like they could change the head from 'oval' back to 'square'.  

I suppose it is what it is - I am simply trying to be prepared as I get ready to dismantle.

Thanks,

Chuck Taylor
1970 280SL #14076
Falls Church VA

[113gray]

I wonder if someone wanted to disguise the head as being from an SE rather than an SL. From JA's excellent chart that Naj provided, it appears the "08" is the only difference. Perhaps, that was what Naj was suggesting.
On another tack, I hope you'll keep us up on the progress w/ your head rehab project. Last summer I was faced w/ this possibility of head work for a similar engine & started looking for competent machine shops in eastern/central Virginia. To my surprise, they were hard to find for MBz engines. Fortunately, I was able to solve my problem w/ a fresh head gasket which I installed myself. So, I will be among those interested as you proceed, particularly if you find the necessity to do more than replace valve stem seals.  -JP-