om617 into 1972 280 SE
 

I am in the process of acquiring a mostly solid '72 280 SE for my wife. It has a mechanically injected gas engine and we would prefer it to be diesel. Would the OM617 be a good candidate and if so, which automatic Overdrive transmissions would be the most simple to swap in. I'm okay with adapting other brand parts. My fj40 is a prime example. It is currently getting a military diesel engine.

I would be buying the car from the original owner who was a vehicle mechanic prior to retiring.

Thanks,

Matthew
MC Designs Offroad

Some one posted on here that the oil pan hit the sub frame.Could be modified???

You are embarking on a research project. If you're doing the work, it's feasible. If you are paying somebody else, it's gonna cost you. However, the results will be a very nice car with a diesel motor in it and if you like diesels, you'll be all right.

There's another thread active in this area from somebody looking for a gas engine like yours. If yours is in good shape, please be sure it gets into the hands of somebody that can use it.

With the OM617a (the turbo 300SD/300D motor), you can run into problems with the intake/exhaust hitting something, the oil filter hitting something or the oil pan.

There are different oil pans between the W116, W126 and w123 cars that can supply a used motor and there are different intake/exhaust setups. Thankfully all are interchangable when the need arises. Regarding the oil filter setup, there are threads in the diesel forum that describe a relocating kit for the oil filter, should it conflict with your steering box.

The W108 cars (yours) have two styles of steering boxes, the straight 6 cars and v8 cars have different setups. You might find no problems on a v8 car. You might find it a royal pain to do a 6 cylinder one.

Lastly, you might find the late 80s, early 90s 2.5l 5 cylinder turbo motor to be a more suitable swap. Also, make sure the transmission attached to the diesel stays with it during the swap. You will have to recut the drive shaft no matter what you do and set up hybrid wiring and exhaust and engine shocks, but that's all "straight forward" fabrication.

-CTH

Other than a Euro only 5speed manual, there is no overdrive transmission that will bolt to a 617 that I am aware of.

If you went with a later 60X like cth350 suggested you could try to use a 722.5 or 722.6 with some type of aftermarket controller like whipplem104 does in the performance section. Those transmissions will bolt up, but they won't just work they to will require some creativity. 5 speed manuals with overdrive that bolt to the 60X are also a much easier find than the 5speed for the 61X.

It's not an overdrive transmission, but the simplest to swap in would be a 722.118. It's shifted all by Bowden cable/rod, so there's no vacuum stuff to mess around with.

Phil Forrest