Alloy heads on a 617? and other engine lineage questions
 

Hello! I had always been under the impression that the 616 and 617 were very similar engines, with the major change being an extra cylinder (and all of the space issues and crank issues that come with it), and that the 603 was a ground-up new design, and that most MB diesels built after the 603 were based on it (the 2.2l, 2.5l {did the 190D 2.5l and the 300D 2.5l use the same engine?}, and 3.5l engines come to mind).

Now someone on another site's saying that there were 616 and 617 engines built with an alloy head (I'm guessing he means aluminum?), and that the 603 and later engines were based on the 617. Does this make sense? Also, how does the new CDi engine fit into this?

Thanks!

LOL - alloy if you call cast iron an alloy. Unless someone did a custom head the 616/617 engines had an all cast iron head - just like the engines built 50 years ago. I think someone is blowing smoke on this one.

According to this guy, the alloy-head engines were used in marine applications. Also, according to this guy, they had a 240D witha factory turbo that was used in marine applications.

Offhand, I think you're right, Jim, and I'm looking for some ammo... :D

BTW, here is a link to the thread on the other site where this discussion is taking place...towards the bottom. LMK what you think :)

Thanks!

I heard the 85 617s had alloy heads. I havn't taken a magnet to mine yet....

if im not mistaken i beleive mercedes did make chngs to the head when they developed the turbo diesel engine.it is made of a different type of material although i dont think it contains aluminum.vw followed suite with their first turbo diesels.the heads were made of a different material to withstand the higher thermal loads associated with turbo charging

The guys to answer your question is Mercedes NA-

Write them!! I'm nearly positive he is mistaken. To my knowledge there was never any aluminum alloy heads for 616/617's and no factory turbo charged 616 applications.

Marine stuff ussually is not lighter... it was just not emission regulated for many years.

Michael

Re: Alloy heads on a 617? and other engine lineage questions
 

From the mid 80s through early 90s...

The 2.0 and 2.2 4-cyl Diesels are 601s

The 2.5 5-cyl Diesels are 602s

The 3.0 and 3.5 6-cyl Diesels are 603s

Then came a new range of Diesels including the 3.0 6-cyl 606 offered in the US.

Sixto
91 300SE
87 300SDL
83 300SD