The Chilton manual and the Haynes manuals are "OK" but the FSM (Factory Shop Manuals are the best. best way to find them is on E-Bay. I picked all 5 for the 123 for around $225. some ont e-bay seem to think they are gold plated price wise.

this will help you http://mercedes.thatchermathias.com/

the 617.951 is used in the 300SD 81 - 85
the 617.952 is used in the 200D 82 - 85, both are turbo charged.

the differences are the arm from the block to the motor mounts, and the oil filter housings.
theSD uses an electric oil sending unit, the D uses an oil line to the oil pressure gauge.
may be one or two other minor issues. the long blocks are the same.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works