I am looking at purchasing a 1981 300SD Turbo. This car has 220K miles on it and in very good condition, asking price is $2800. How do I know if the engine and trans are in good shape? About what gas mileage should I expect?

Welcome to the forum. I am a relatively newbie here, myself. I would advise you to READ. Do a search in this forum on the topics you asked about. There must be 50 pages of posts about how to tell if a diesel is in good shape. The archives in this forum can provide you with more information about diesel Mercedes than you could imagine.
In a nutshell, Don't be overly impressed by the condition of the interior. If the seats are covered with MB Tex, they will always look good. Leather, especially if not maintained with show a lot of cracks.
Cars with known service histories are a bonus.
Realize that for the first year you may be performing a lot of maintenance that the previous owner deferred.
With the engine warm and running, remove the oil filler cap and observe the stream of exhasut gases flowing out of the cap. It should look like a tea Kettle on boil; not like an old steam locomotive at full throttle.
Look for rust.
Rear floor, and sills, and jack points.
Read the old posts.
Read the old posts
search the forum.

Thanks for the good advice. Looks like I have a lot of reading to do.

in the bottom of the doors and under the battery tray.

Expect 25-27 mpg when driven gently once the car is in a good state of tune.

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1985 300SD, 203,000 miles, dark blue

Lil Sarah says: "Poor old Grandma Blue Car...She's sad."

"Considering 81 300std for first MB"

Well they aren't an std but once you get one you may have it for life

My problems with rust on my 79 were in the back lower corners of the rear wheel wells. I think this was due to a leak in the trunk weather striping that I could never locate.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

http://ecomodder.com/forum/fe-graphs/sig692a.png

...My problems with rust on my 79 were in the back lower corners of the rear wheel wells. I think this was due to a leak in the trunk weather striping that I could never locate....

Look closely and you may find you have a cracked tailight lens.

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1985 300SD, 203,000 miles, dark blue

Lil Sarah says: "Poor old Grandma Blue Car...She's sad."

1. hoodpad still attached? about 80 bucks.
2. are the panels around the front jack points still there?
3. is that front fender loose? it may be rusted underneath.
4. pull the cover off the spare and pull the tire. can you see sunlight?
5. pull the cover on the other side where the jack and emergency kit are. same question.
6. are the outside lips of the wheel arch rusted thru?
7. you really need to drive the car. does it track straight?
8. rock the front fenders. do the shocks squeak? when you look at them is there fluid leaking from them?
9. does the motor have oil all over it? is the bottom covered in oil? bad leak somewhere. usually the turbo return line from under the air cleaner.
10. speaking of the air cleaner does it rock? broken mounts. cheep.
11. is there rust around the rear window?
12. does the rear hatch stay up w/o using a broom handle? nabout 30 bucks each.
13. doesa the car have a sunroof? get a couple gallons of water and pour one over the front corners. if water comes into the car the drains need work. this involves taking the headliner apart. i did it. my wife was very helpful.
14. pull the battery. is the tray in one piece?
15. is the bulkhead under the battery tray still one piece or has a hole opened up? expensive weld job for a trained person.
16. clean out under the hood springs. you can stand up the hood. is the area under the acqumulated debris still in one piece? more welding.
17. just for snicks, does the radio work? does the antenna go up and down. its electric.
18. do the heater controls work? it might just be a connection issue like on mine or it might be the complicated controls. i don't know. mine is horizontal. the complicated one is vertical. a new one is expensive.


4 and 5 directly relate to the wagon but, go ahead, get wacky, remove the trunk mat and take odd the plastic inner fenders. what is there? maybe a cb antenna lead?

if no service records plan on changing
1.oil
2 oil filter
3 primary fuel filter
4. secondary fuel filter
e. the air cleaner filter
f. the glow plugs.
5. the battery
6. the black dirty fuel return lines(they sb grey and fuzzy)

much more but gotta go to work.

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currently
[1981 300 td tdidi 165500 dark brown/palamino-Brownie-mine-3k miles of ownership
1983 240d 162+++ Anthricite grey w/ henna red interior and hella lights-wifes car-Red

the above two cars are for sale
and can be seen on the cars for sale thread here. pix also available.


240d-144+ Manilla Yellow w/ palmino interior-greasecar kit-Blondie-the college kids car

23" gt 21 speed still on original tires-still got the nubs
21" khs tandem

[QUOTE=ConnClark]"Considering 81 300std for first MB"

Well they aren't an std but once you get one you may have it for life
QUOTE]

Ow, my sides. That's some funny stuff!!

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine