Can I use a donor 1979 300SD Turbo motor in a 1983 300SD ?
The 79 lists 617.950 and the 83 says 617.952.

I can visually see that the vacuum pump is very different (even different from my 1980 and the 81).
Guessing I can switch in the newer vacuum pump.

Turbo looks the same, same location of alternator, AC compressor, Power steering pump.

So, does anyone think this engine is a good donor for any 1981 to 1984 Turbo engine ?

Thanks for all your help.

__________________
80 300D 340K Owned 30 yrs
83 300SD 440K Owned 9 yrs - Daily Driver 150mi/day
02 Z71 Suburban 117,000
15 Toyota Prius 2600 miles
00 Harley Sportster 24k
09 Yamaha R6
03 Ninja 250

IMO, that swap is doable, but I don't think the vacuum pumps interchange. There will be some issues with vacuum (no EGR on the .950). Going the other way ( .952 into a W116 chassis) does not work unless you change the upper oil pans. The .950 had less horsepower until 1980, though, and there may be issues with non-hardened cams.

__________________
80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)

The interesting thing is that although it lists 10 less hp, my 79 SD is faster throughout the whole range then my 85 300D.

__________________
1959 Gravely LI, 1963 Gravely L8, 1973 Gravely C12
1982 380SL
1978 450 SEL 6.9 euro restoration at 63% and climbing
1987 300 D
2005 CDI European Delivery
2006 CDI Handed down to daughter
2007 GL CDI. Wifes

Your 79 has a lower final gear ratio than your 85.