Cylinder Head interchageability

[John A. Dean]

My 69 280 SL, which runs great, has the euro cam and seems to have a sound valve train, just developed a coolant cloud plumming from the exhaust.  After pulling the head, a crack in the number 3 piston exhaust port was found.  My local machine shop doesn't believe that they can fix the problem. Obviously, I would like to repair and keep my original head.
Options:
Does anyone know somewhere where this kind of work could be done with reliable results? If I can't do that thenI may have access to a 250 SL parts car with a running engine, fuel injection problems and a totally rusted out body.  But I don't know about head interchangeability. If that head isn't interchageable then I will have to bite the bullet and buy a used head.  What is the going rate for a used head or a rebuilt head? Is there any advantage of one over the other?  Can anyone recommend a source?

Thanks

[ja17]

Hello John,

Sorry to hear about your problem. a crack in one of these heads is very very unusual. 
No 250 series will work on your  engine. In fact there are two types of heads for the 280 series engines and you must use the correct 280 head.  The good news is that the 280SE sedans of the era used the same heads.  But you will need to make sure  it is the correct version also. Check my cylinder head chart to make sure you get the right one.   Prices will vary widely on used heads depending on your luck, where you find it and its condition. Good used "uncut" heads are the most desirable.   Plan on reconditioning any used head you find before installing it. 

Notice that the 280SL heads are  split into two groups (early ones have "square" combustion chambers, the later ones have "oval "combustion chambers). You must find one in your group. Look below the rear spark plugs for your head casting number.

[Cees Klumper]

New heads are still available, hope this link to the SLS site works. You need to click on the little '1' number next to the drawing of the cylinder head:

http://www.sls-hh-shop.de/index.php/cat/c3_Mercedes-Benz-230-280SL--R113-.html#cat_57_position_1_prod_0

I've sold a good used, uncut head a few years ago, for EUR 900, which I thought was reasonable considering the prices of new, now either EUR 2,200 or EUR 3,200, depending on the type. But as Joe indicates, if you find a good sedan donor car or engine, you might be able to pay less.

Note: at the Essen classic car show yesterday, we visited the (quite extensive) Mechatronik stand and they had a head on display that they had welded to correct some corrosion. So apparently there are some shops out there that do do some repairs to these heads.

[John A. Dean]

Thanks for your expert replies.  I actually found the head  chart, after asking my question, deep in an old thread.  I didn't know about the 280SE head interchageability, however. 
My local shop is checking around their sources to see what options they can find, I thought that I would send feelers out also, or at least feel that I can speak to them from some basis of knowledge.

thanks again.

I will post the final outcome, later, just in case anyone else faces this problem iin the future and needs some point of reference.

[Ron]

John, I sent you a PM on where to find a used head, with "square" classification.  Good luck, Ron

[John A. Dean]

Thank you Ron, I have contacted the seller with some questions.

There is a guy in Atlanta with experience welding Mercedes heads who feels confident that he can repair my head.  The head has been sent to him for an evaluation.  I am still waiting to hear from him.