617 turbo longblock into 617 nonturbo application? - PeachParts Mercedes-Benz Forum

RobTheMod · #1 02-27-2007, 01:46 AM

Hmmm, I'm trying to figure out why this won't work.

I have possibly the nicest original W115 300D in the US and it has a bad engine. This has led me to put it up for sale but no one seems to want it even around $800... everyone keeps asking if the W123 turbo 617 they have (in a rusted, bad transmission, etc. 300Dt) will fit. I see no reason it won't, *except* oil filter setup, and of course, the TURBO. Which, based on my measuring the 617.951 in my 1981 300SD and the bay in the '76, will not fit, period.

Since this has scared off everyone on forums, and on craigslist, from buying this 300D, and I now have access to a salvage title 1978 300SD (W116, turbo) with a strong engine, can *I* put this engine, using the oil filter assy, NA engine manifolds, etc, into the W115 to make a runner of it, or is there some other gotcha like a flexplate which won't bolt up to the torque converter from the W115 transmission?

I say *I* because I've now spoken with at least 4 people who find putting a W123 turbo engine minus turbo in to be beyond their skills, am I missing something here? Otherwise, I may need to put this on eBay, and when it sells for well over $1k, you'll all complain about how expensive these are! (j/k)...

#2 02-27-2007, 02:08 AM

The hardest part would be converting the oil filter body to make it remote mounted.

It has been done, however, I can't find the picture I used to have of the remote mount assembly/plate.

Rashakor · #3 02-27-2007, 01:12 PM

you would have the same exact challenges with the om617.950 than with the om617.951 or 952.
The fact that the engine comes from a 116 or a 123 has little influence. I would try to transplant the engine with its transmission and differential.
I would try to pair the w116 engine with the oil filter set up of the w115 or get a completly aftermarket bypass filter and don't bother with the antiquated and highly unpractical set up in the W115.

Finally i would try to transplant the turbo in a different set up (if will require some creative piping!!!). All the om617.95X are going to be very sluggish without turbo (compression of only 17:1). Good luck.

vstech · #4 02-27-2007, 01:35 PM

Quote:

Originally Posted by Rashakor

All the om617.95X are going to be very sluggish without turbo (compression of only 17:1). Good luck.

Is that right? I was under the impression both 617's had 22:1 CR... How does it start with such a low CR?
John

Rashakor · #5 02-27-2007, 02:15 PM

well actually 17 admospheres is the minimum for diesel ignition. Let me check the datum exactly but i know for sure that compression is significantly lower with the turboed head.

Now, that raises another interesting question: could you use the 617 turbo short block assuming the 617 NA head is fine? in which case you would have a true NA om617 engine with beefy pistons!!!