W115300D Has a Knock, Need a Donor Engine
 

Turns out my 300 dollar '75 W115 300d has a knock -top of number five piston is bright and shiny from making contact with the head, If lucky, the crank journal will be fine and we can install new rod bearing, etc or it might be wrist pin possibly. Anyone out there have any leads on a running '75 or '76 w115 300d engine? Help! I wish the 123 engine would work but the block set up is different . . . . .

I am about to start restoring my 1975 W115 300D. I will be doing a leak down test to try to determine the cause of my excessive oil consumption. If it just needs top end work, I will either redo my current cylinder head, or use a spare head from my former 1976 W115 300D.

If it need bottom end work in addition to the head work, I will be in the same boat as you.... Looking for a good replacement engine.

The W115s are, of course, fairly hard to find. The early W123s (pre-turbo) are pretty similar to the W115s. You appear to think that they wont work. What is your basis for that conclusion.... Assuming that is what you believe.

While there are slight differences between the two, I disagree with that conclusion: I believe it will work. If I do need to replace the engine, and if I can't locate a W115, I have an early W123 available that I plan to buy and swap in.

I am interested to know your thoughts, in case I have overlooked something. Although I think I am correct, I could be mistaken. I would much rather find out sooner than later.

:)

a 617.912 would have to moded to fit into a W115. Oil filter housing from 123 wont fit in 115 engine bay.

Remote oil filter? Or housing from a van motor--they point down and back.

A remote oil filter can be made. It would look something like this.

The 617 engine was slightly modified to bring the oil filter topside for the W123. If the topside filter will not fit in the W115 engine bay----- and I am not sure that it won't--- is there a reason that the later engine cannot be re-modified to accept the original W115 style oil filter housing unit.... Since I have that available from my engine?

I thought that all OM617's were equal but not the case -the w115300d has a different block set-up (explained to me by Kent Bergsma so some very key mounting points are missing, the oil filter location issue has been discussed many times on this site -

see pic in previous post, yes, it can work but it was explained to me to still be a pita -

The two videos below are both W115s with turbo. One is diametricalbenz's car. ASFAIK, all the turbo engines had the topside-mounted oil filter. However, I don't see the topside oil filter on either one of these. I don't know why.... whether it was changed due to a fitment problem, or what.

Perhaps someone can shed some light on this. I do see where diametricalbenz made a plate... but it doesn't show where the filter is located. My thought was that, if necessary because of fitment of the topside filter into the W115 chassis, I could simply attach my old style oil filter unit right where he has fitted the adapter plate.... which I believe is exactly where mine is fitted on the older engine.

Am I wrong on this? Any input greatly appreciated.


http://www.youtube.com/watch?v=uOew1zdeJHg

http://www.youtube.com/watch?v=863F7yeDdHo&feature=related