When I had diesels I went through starters. I went to the discount chains for starters and always took them back. I got really good a R&R'ing 240D starters in less than a 1/2 hour. The problem was they were all not up to the ratings necessary to crank a Mercedes when cold.
I finally gave up with deals and got a quality rebuilt specically for a Mercedes diesel. Never replaced it again.
Get one from FastLane or check with a local auto electric rebuilder. Tell them it has to be for a Mercedes diesel, they'll know exactly what and why you are saying this.
This is a case where cheaper isn't better.
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)