This is a diagram I have of the crank and its related parts.
The woodruff key has a part# 6049910168.

Attached Thumbnails

 

__________________
DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012

005 A6030311301 6030300501 - Crankshaft
005 A6030300501 6030300601 - Crankshaft
005 A6030300601 6030300901 - Crankshaft
005 A6030300901 6030301001 - Crankshaft
005 A6030301001 6060310101
+001 A6019970410 - Crankshaft
005 6060310101 001 Crankshaft
008 6019970410 001 Pin
017 A1089910067 6049910168 - Woodruff Key
017 6049910168 001 Key Crankshaft Gear And Hub On Crankshaft
023 A6010520003 6060520003 - Crankshaft Gear
023 6060520003 001 Crankshaft Gear
029 A6010300108 1040300008 - Hub
029 1040300008 001 Hub Pulley
032 000007008202 001 Cylindrical Pin
038 A1279930026 6049900040
+001 A0069903701 - Disc Spring
038 6049900040 001 Washer Hub To Crankshaft
041 N000961018020 0069903701
+001 A6049900040 - Screw
041 0069903701 001 Screw Hub To Crankshaft
047 A6030320304 6030320404 - Pulley
047 6030320404 001 Pulley *036
053 6030300303 001 Vibration Absorber Vibration Absorber
062 000912008134 006 Screw Vibration Absorber And Pulley To Hub
065 N000125008418 000125008443 - Washer
065 000125008443 006 Washer Vibration Absorber And Pulley To Hub
086 A6030300705 6030301505 - A Flywheel
086 6030301505 001 A Flywheel
092 1020320205 001 Ring Gear
101 A6030320006 1020320606 - Follower *009
101 1020320606 001 A Follower
113 A1020320071 1119900312 - Screw *405 *042
113 A1119900312 0019909112 - Screw
113 0019909112 008 Screw Follower Disc,washer And Flywheel To Crankshaft *015 *043
----- 6010332202 007 Crankshaft Bearing Half Lower;standard 58.00 Mm *014
131 A6030300540 6030301040 - Crankshaft Bearing *011
131 A6030301040 6010300540 - Crankshaft Bearing
131 6010300540 007 Crankshaft Bearing Parts Kit,standard 58.00 Mm *012
131 A6030300640 6030301140 - Crankshaft Bearing *011
131 A6030301140 6010300640 - Crankshaft Bearing
131 6010300640 007 Crankshaft Bearing Parts Kit,repair Size I 57.75 Mm
131 A6030300740 6030301240 - Crankshaft Bearing *011
131 A6030301240 6010300740 - Crankshaft Bearing
131 6010300740 007 Crankshaft Bearing Parts Kit,repair Size Ii 57.50 Mm
131 A6030300840 6030301340 - Crankshaft Bearing *011
131 A6030301340 6010300840 - Crankshaft Bearing
131 6010300840 007 Crankshaft Bearing Parts Kit,repair Size Iii 57.25 Mm
131 A6030300940 6030301440 - Crankshaft Bearing *011
131 A6030301440 6010300940 - Crankshaft Bearing
131 6010300940 007 Crankshaft Bearing Parts Kit,repair Size Iv 57.00 Mm
136 6010300062 002 Guard Plate Parts Kit 2.15 Mm
136 6010300162 002 Guard Plate Parts Kit 2.20 Mm
136 6010300262 002 Guard Plate Parts Kit 2.25 Mm
136 6010300362 002 Guard Plate Parts Kit 2.35 Mm
136 6010300462 002 Guard Plate Parts Kit 2.40 Mm

*009 First Exhaust Stock Of Old Parts In Place Of 102 032 03 06
*011 Exhaust Stock Of Old Parts Up To Engine
912 10/50,20/60 048567
912 12/52,22/62 032081
913 10/50,20/60 000570
913 12/52,22/62 000575
950 12/52,22/62 000654
963 12/52,22/62 001366
*012 When Ordering, Please State Additional Code: 52 = Blue; 54 = Yellow; 56 = Red
*014 When Ordering, Please State Additional Code: 57 = White; 58 = Violet
*015 Up To Engine:
912 10/50,20/60 053007 Except For
052037, 052091, 052124, 052184, 052191, 052254, 052281, 052457, 052582- 052584, 052588- 052589, 052608, 052614,
052621, 052669, 052684, 052697, 052713, 052720, 052756, 052759, 052775, 052831, 052836, 052867, 052880- 052884,
052909, 052915- 052919, 052922- 052925, 052942- 053006.
*036 From Engine: 972 002098
*042 Up To Engine:
960 054254
971 016730
972 003808
*043 From Engine:
960 054255
971 016731
972 003809
*405 Only Replaceable By The Set

__________________
DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012

With the 2nd pic of post 5, it looks like you can really see where that smaller half moon woodruff key wore past the pulley groove.....

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

Yeah, that's the part number I used for the key at the dealer. And they gave me the sliver, go figure...

__________________
Jason

00 Subaru Legacy (fun wagon)
96 Nissan Sentra (disavowed)
82 300SD (garage queen, will run again hopefully)
87 300DT (Gone: 10/15/2010)

The crank looks OK but its hard to tell. You need to clean everything up, so you can see what you have.

Looks like you may have gotten lucky and just need a new damper.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Having just gone through a job of removing the front cover on a 1986 2.3-16 with my son this summer, I can tell you the Woodruff key has to fit really tight in the slot in the crank. No wiggle. So get a new Woodruff key and see how it fits. It should be very tight. Almost hard to get in. Until you try, you won't know and those photos don't look encouraging to me.

I do not know if this car has a front cover or not, but if it does you might consider removing it to get better access if the Woodruff key is loose or worse. If you can get access you might cut another keyway 180 degrees out. I would not try welding the crankshaft.

Good luck, you have a challenge ahead of you if that keyway is as munged up in real life as it looks in the photos. Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

It does have a cover.

Attached Thumbnails

 

__________________
DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012

Well, after getting the new vibration damper and pulley, I realized those aren't the parts I need. I need the hub that connects the crank snout to the vibration damper. And upon inspection, the dowel pin is still in tact

And I decided to take a picture of the "woodruff key" which is so worn away (although not sure what it was to begin with) that it doesn't even resemble a key.



and another picture showing the detailed wear on the hub


Now I'm trying to decide on keeping it, parting it (it'll be hard since its my first car) or just selling it as is

__________________
Jason

00 Subaru Legacy (fun wagon)
96 Nissan Sentra (disavowed)
82 300SD (garage queen, will run again hopefully)
87 300DT (Gone: 10/15/2010)

From my experience with these engines I have to tell you that your crankshaft is severely damaged and needs to be replaced. I am currently trying to gat my crank shop to fix one for me. All total I have seen three of these faliures.The large bolt holding the hub to the crank comes loose over time after not being tightened properly. It is impossible to get it tight enough without either the tool to lock the engine or a very large impact gun. Sorry to bring you bad news.

Your crank needs to be replaced.....The groove is too worn. Sorry.
What kind of shape is the rest of the car in?

The car's condition is poor, really. Its a salvage title and at the moment, it looks alright but the hood isn't lined up/painted.

I'm just trying to decide whether to part it out or to just sell it as is. I honestly don't think its worth putting money into.

__________________
Jason

00 Subaru Legacy (fun wagon)
96 Nissan Sentra (disavowed)
82 300SD (garage queen, will run again hopefully)
87 300DT (Gone: 10/15/2010)

If it's a case of either mending this fault, or scrapping the car, why not try a repair?

For example, you could;

a) weld the pulley onto the end of the crank
b) Drill a hole down the interface between the pulley and the crank, and then use the shank of another drill of the same size to form an in-situ fitted key
c) Weld repair the key slot in the pulley, and file it back square, weld the key into the crank nose and file back square

I'm sure there are many more ideas which will upset the purists (or those with more money than sense!), but if it stops the whole car being scrapped, then perhaps it's worth it?


- ideally, one day, I would like to have more money than sense - there's not much I can do to improve how much sense I have been given!

How about?
http://seattle.craigslist.org/see/pts/417417863.html

__________________
DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012

Number_Cruncher, is it possible to do these repairs while the crankshaft is still in the engine?

And OMG lietuviai, thanks for the craiglist posting! I'll inquire about it.


Ideally, I'd like to keep the car since it is my first car and its a 603. But there seems to be enough wrong with it that this is the straw that's going to break the camel's back.

BTW, I've seen more italian exotics than I have 60X cars.

__________________
Jason

00 Subaru Legacy (fun wagon)
96 Nissan Sentra (disavowed)
82 300SD (garage queen, will run again hopefully)
87 300DT (Gone: 10/15/2010)

You need a new hub and key. Without a fix the car isn't worth much so you have little to loose. I'd clean the crank up and fit a new key along with a dab of JB Weld and a new hub.
This is a common problem on older Miatas and the JB Weld along with new parts seems to work. And this is done by owners wishing to keep their cars, not foist them onto others.