what versions of the NA 617 will fit within the W115? - PeachParts Mercedes-Benz Forum

citationtech · #1 08-03-2015, 06:08 PM

I've heard that the topside oil filter housing of the 123's 617.912 will not fit within the W115's frame rails. The W115 617.910 seems to be difficult to get a hold of plus the .912 has a few nice internal improvements.

I bought my '76 300D with a bad HG (#2 & #3 GPs have rust on the heateing element) and I just found badly worn (scored) cam lobes and rocker arm faces on #1 & #2, so I'll probably have to throw an engine at it. Waiting on my friend to return my engine lift so I can get this HEAVY head off and see how she looks inside.

Check out the wear on the rocker face!

Walter K · #2 08-03-2015, 08:35 PM

It is hard for me to tell from the photos how worn the cam lobs are. Looks like however that the engine has been upgraded with carbide on the rocker arms, so the cam should have been upgraded as well. That car didn't come with the hard cam or carbide rockers. With a mirror, see if you can read the number on the back end of the cam. IIRC, the ductile cam is "00".

If the cam is a soft one, you might be able to find a hard one to replace it (with towers). The cam lift is higher, so you will need to change the valve springs out, but you are taking the head off anyway.

Fwiw.

Regards,

W

gmog220d · #3 08-03-2015, 10:21 PM

Nice looking car. Is it dark blue, or black?

Anyway, I think there's a good chance you could use a 617.912 in your car. Unless I'm missing something all you'd need to do is swap over the oil filter assembly, manifolds, water pump housing, etc.

NZScott · #4 08-05-2015, 02:22 AM

The blocks are different casting between the .910 and .912. Most people swapping later engines into these cars just remotely mount the oil filter.

And if you're going to all the trouble of the above, maybe consider a turbo .95x engine?

t walgamuth · #5 08-05-2015, 06:06 AM

I think there are other interferences besides the oil filter, such as the ac compressor. I'd be sure that a new engine is needed before giving up on yours and then if needed search for an early 617 that will fit between the narrow rails.

citationtech · #6 08-06-2015, 09:33 PM

Quote:

Originally Posted by NZScott

The blocks are different casting between the .910 and .912. Most people swapping later engines into these cars just remotely mount the oil filter.
I hadn't thought about a remote filter relocation. I'm trying to keep this car mostly;y original while adhering to a budget.

And if you're going to all the trouble of the above, maybe consider a turbo .95x engine?

I thought the same thing but the NA 617 found in the 123 won't fit without rework, let alone the turbo charger and associated components with the turbo 617s

Quote:

Originally Posted by t walgamuth

I think there are other interferences besides the oil filter, such as the ac compressor. I'd be sure that a new engine is needed before giving up on yours and then if needed search for an early 617 that will fit between the narrow rails.

It's funny you mention the compressor. I was stunned at how many fasteners hold the AC compressor bracket to the engine, I think there were 8 while the compressor sat on 6 studs!

t walgamuth · #7 08-06-2015, 09:45 PM

Quote:

Originally Posted by citationtech

I thought the same thing but the NA 617 found in the 123 won't fit without rework, let alone the turbo charger and associated components with the turbo 617s

It's funny you mention the compressor. I was stunned at how many fasteners hold the AC compressor bracket to the engine, I think there were 8 while the compressor sat on 6 studs!

I call that bracket that holds the early 616 617 compressors up high on the engine the Frankenstein bracket.

In the 123 the compressor sits down low just in front of some suspension parts IIRC. That's why the 240 engine sits with its front in the same place as the 617 engine I suppose.

jay_bob · #8 08-07-2015, 07:49 AM

I would wait and see how the block looks first after taking the head off. You may be only looking at a head job to get things right again.

Remember these are all-iron engines so your chances are good that it is just a blown HG and some wear on the cam that can be machined off.

NZScott · #9 08-08-2015, 04:14 AM

Sorry, good point, A/C compressor might be in the way....never even seen a diesel Merc with AC over here yet

Getting a rebuilt head is definitely worth it, just remember your older pistons won't work with newer camshafts because they have more valve lift.