Hey everyone I have a 1980 w116 300sd. It does not have an engine/transmission but I have an engine and transmission from a 1983 w123 300D.
Is this engine and transmission a direct drop in for the 1980 300sd?
The upper oil pan on the 300D's engine is probably a different shape and won't fit in the W116, as the upper oil pan would hit the cross-member. But, you might be able to use an upper oil pan from a 1970s non-turbo 300D. The W123 transmission will likely be geared differently than a W116 transmission, and you may run into fitment issues with shift linkage and driveshaft length, not to mention wiring.
As Squiggle Dog said, there will be clearance issues with the engine from the 83 W123 300D, and possibly the tranny as well.
You first will need to swap a 1980 W116 upper oil pan onto the 83 OM617A engine.
The 1978 and 1978 W116 300SD upper oil pans have the single oil return nipple for the turbo oil return tube.
Only the 1980 W116 300SD upper oil pan has the two oil return nipples for the turbo oil return tube and the crankcase oil seperator return tube.
I have on hand two 1980 upper oil pans to eventually install ln my 300SDs.
PM me if you end up needing to acquire one of them for your project.
Also, the engine mounting arms are probably different.
Sounds like it's not worth the trouble. Where can I purchase a 1980 300 SD engine? Is there a specific model or code that identifies the engine as specific to the 1980 300SD.
Engine: OM617.950
Transmission: 722.120
Both are specific to the 1978-80 300SD
In all honesty it will almost certainly be more worth buying an entire car with a running engine and transmission. Unless you are opting for a rebuilt engine 4K-6.5K(check out reinventthewheel + shipping. And your have an excellent supply of every part you'll need to keep going.
Another note the w116 300SD transmission was the last year where a speedometer cable was used (went from the trans tail housing to the instrument cluster for mileage and speed)
Other Atlanta 300SD guy here. I had to reset my phone so I don't have your number anymore, but I may be able to help again. I have 2 working 116 300SD transmissions (one I was told was a recent rebuild) and a 116 300SD engine that has head/compression issues that you could cannibalize for the W116-specific parts.
I have a running 1979 300SD with a good engine and transmission. The valves have been adjusted and she really drives and shifts well. The interior however is toast. I have three Mercedes and I won't be restoring this one. The car can be driven wherever you need to take her. Let me know if you are interested.
If any of you Georgia fellas ever get up to Knoxville please stop by! :)