Hello Folks,
Just purchased a 1981 300SD, 195K.
I am a non-mechanic female but a very fast learner and a mechanically inclined husband- had an appointment with our local, trusted mechanic but realized he hadn't a clue about MB diesels, so, I came to you first. I have run some searches but found it very hard to put all the issues together. I appreciate greatly any knowledge or help offered!

Here are her known issues as I drive her and find her quirks:
-Black (very) smoke on acceleration- cold or warm, often mixed with grey too,
-Rough idle on when first started each day,
-Likes to idle and warm up before I drive her- otherwise will hesitate in low gears,
-Transmission flairs at 1-2 and can sometimes shift hard, sometimes slams into any gear - mutch better if engine is very warm,
-Find oil spots under front part of car where she is parked,
-Thought I found a fuel spot one day after she was idling for a bit toward back of car,
-Oil pressure is pegged at 3 while peddle is pushed, 0 at idle, always,
-Previous owner had oil level over full at cold,
-Dash instruments work when they feel like it (Fuel gage, tach),
-Dash lights very dim or non-existant-rehostat seems crudded up (?),
-Needs some front quarter panels to stop rust.

Good stuff- no failures:
-Power windows
-Locks
-Sunroof
-interior lights (except instrument and buttons)
-Temp gage seems accurate

Have not changed any fluids yet or had any maintanance done, someday want to convert her to WVO, possible SVO.

Once again, I appreciate any help!

K8

81 MB 300SD, Burgandy (Husband calls it the "Wife's Pimp-Mo-Bile", my brother threatens to cover the seats in pink sheapskin, ugghh)
86 Diesel Suburban (speared by a DOT truck- RIP)
70's Diesel Scout International (Fell apart on me while in college- RIP)
79 or 80 MB 240 D Manual ('Rents car when I was young- what got me wanting an MB diesel all these years later- MIA; was baby sh*&t green)
Still wanting a MB manual W123 diesel

lets see.

black smoke under acceleration if not too excessive is normal.

rough running til a bit warm usually is glow plug issues. one or more dead.

leaking fuel is usually return lines. perhaps the end plug even.

the shifting issues may well be vac issues or modualtor issues.

three at speed is normal. zero at idle if accurate is too low. this should be checked by putting a mechanical guage directly on the oil port on the engine. if truly zero the car should not be driven til the reason for the problem is known and repaired.

erratic guages is usually an electrical ground issue. the oil pressure is a mechanical unit so is not affected by electrical issues.

rust in the fenders probably is most effectively fixed by replacing the fenders unless very minor.

good luck

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

AFAIK, the oil pressure gauge on the SD (W126) is electric.