Fellas,

Let me start by saying that I don't own a mercedes diesel at the moment. The last one I owned('86 190D) I sold a couple years back. I am currently courting a 1999 E300D and hope to be the proud owner in the future. I am very interested in fuel economy, and as such in the past I have experimented with higher than normal coolant temperatures and increased MPGs from the change. I am currently(along with 2 others) evaluating a "Hybrid" T-stat for my 2002 VW Jetta TDI. Stock temps for the TDI(ALH engine) is 195 Deg F, and I am now successfully runing between 203-209 Deg F with a 3-4 MPG improvement. The is a link to the Thread on the TDIclub.com so you can read a bit more if interested:

http://forums.tdiclub.com/showthread.php?t=306799


page 4 has some photos of the "Hybrid" unit, and some youtube videos of it's construction.




Since I now hope to have a E300D I wonder what the tolerance is to higher than normal temps on these? I see that the non turbo models ran 85C(185 F), and the Turbo units run 80C(176 F). I am somewhat unfamiliar with the OM606 cooling and oiling systems(though I am curently studying them) and am unsure if they would be able to support the higher temp(195 F) operation.

Specifically, do the 1999 E300D engines have piston skirt oil jets for piston cooling?

Also, how tolerant are the head gaskets, and heads to thermal warpage?



I know this topic can at times get heatedand very emmotional, but I'm just looking for some hard factual information you all may have(that is OM606 turbo specific) or have seen first hand. I realize I may get flamed for this type of heretical thinking. Thanks, and lookin forward to the discussion!



Josh