Earlier today, the key in my 300D wouldn't turn. It does this sometimes.

After some jiggling it finally turned. I promptly removed the tumbler.

The key works fine in the removed tumbler. It doesn't hang up at all.

Does this point to a problem with the ignition switch/lock?

__________________
JWJ
1983 MB 300D - > 430,000 miles - Deep Blue - Bilstein Comforts - 0-60 in 24 seconds - 27MPG
1985 MB 300TD (wagon) - > 275,000 miles - Manila Beige - Thule rack - 0-60 in 18 seconds - 22 - 25MPG
Biodiesel, Mobil Delvac 1, and Viton fuel lines!

Generally yes.
This thread has the information you need.

Ignition Cylinder Tumbler replacement; mixed diesel/gas
http://www.peachparts.com/shopforum/diesel-discussion/142232-ignition-cylinder-tumbler-replacement%3B-mixed-diesel-gas.html#post1065596






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1985 300SD
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